This test case creates an unreadable VMA and my patch assumed
that all writes must be to readable VMAs.
The simplest fix for this is to remove the pkey-related bits
in access_error(). For execute-only support, I believe the
existing version is sufficient because the permissions we
are trying to enforce are entirely expressed in vma->vm_flags.
We just depend on pkeys to get *an* exception, it does not
matter that PF_PK was set, or even what state PKRU is in.
I will re-add the necessary bits with the full pkeys
implementation that includes the new syscalls.
The three cases that matter are:
1. If a write to an execute-only VMA occurs, we will see PF_WRITE
set, but !VM_WRITE on the VMA, and return 1. All execute-only
VMAs have VM_WRITE clear by definition.
2. If a read occurs on a present PTE, we will fall in to the "read,
present" case and return 1.
3. If a read occurs to a non-present PTE, we will miss the "read,
not present" case, because the execute-only VMA will have
VM_EXEC set, and we will properly return 0 allowing the PTE to
be populated.
Test program:
int main()
{
int *p;
p = mmap(NULL, 4096, PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
p[0] = 1;
return 0;
}
Reported-by: Andrey Wagin <avagin@gmail.com>, Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dave Hansen <dave@sr71.net> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mm@kvack.org Cc: linux-next@vger.kernel.org Fixes: 62b5f7d013fc ("mm/core, x86/mm/pkeys: Add execute-only protection keys support") Link: http://lkml.kernel.org/r/20160301194133.65D0110C@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:40 +0000 (13:02 -0800)]
mm/core, x86/mm/pkeys: Add execute-only protection keys support
Protection keys provide new page-based protection in hardware.
But, they have an interesting attribute: they only affect data
accesses and never affect instruction fetches. That means that
if we set up some memory which is set as "access-disabled" via
protection keys, we can still execute from it.
This patch uses protection keys to set up mappings to do just that.
If a user calls:
mmap(..., PROT_EXEC);
or
mprotect(ptr, sz, PROT_EXEC);
(note PROT_EXEC-only without PROT_READ/WRITE), the kernel will
notice this, and set a special protection key on the memory. It
also sets the appropriate bits in the Protection Keys User Rights
(PKRU) register so that the memory becomes unreadable and
unwritable.
I haven't found any userspace that does this today. With this
facility in place, we expect userspace to move to use it
eventually. Userspace _could_ start doing this today. Any
PROT_EXEC calls get converted to PROT_READ inside the kernel, and
would transparently be upgraded to "true" PROT_EXEC with this
code. IOW, userspace never has to do any PROT_EXEC runtime
detection.
This feature provides enhanced protection against leaking
executable memory contents. This helps thwart attacks which are
attempting to find ROP gadgets on the fly.
But, the security provided by this approach is not comprehensive.
The PKRU register which controls access permissions is a normal
user register writable from unprivileged userspace. An attacker
who can execute the 'wrpkru' instruction can easily disable the
protection provided by this feature.
The protection key that is used for execute-only support is
permanently dedicated at compile time. This is fine for now
because there is currently no API to set a protection key other
than this one.
Despite there being a constant PKRU value across the entire
system, we do not set it unless this feature is in use in a
process. That is to preserve the PKRU XSAVE 'init state',
which can lead to faster context switches.
PKRU *is* a user register and the kernel is modifying it. That
means that code doing:
could lose the bits in PKRU that enforce execute-only
permissions. To avoid this, we suggest avoiding ever calling
mmap() or mprotect() when the PKRU value is expected to be
unstable.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Chen Gang <gang.chen.5i5j@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave@sr71.net> Cc: David Hildenbrand <dahi@linux.vnet.ibm.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Piotr Kwapulinski <kwapulinski.piotr@gmail.com> Cc: Rik van Riel <riel@redhat.com> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Vladimir Murzin <vladimir.murzin@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: keescook@google.com Cc: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210240.CB4BB5CA@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:37 +0000 (13:02 -0800)]
x86/mm/pkeys: Create an x86 arch_calc_vm_prot_bits() for VMA flags
calc_vm_prot_bits() takes PROT_{READ,WRITE,EXECUTE} bits and
turns them in to the vma->vm_flags/VM_* bits. We need to do a
similar thing for protection keys.
We take a protection key (4 bits) and encode it in to the 4
VM_PKEY_* bits.
Note: this code is not new. It was simply a part of the
mprotect_pkey() patch in the past. I broke it out for use
in the execute-only support.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210237.CFB94AD5@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:36 +0000 (13:02 -0800)]
x86/mm/pkeys: Allow kernel to modify user pkey rights register
The Protection Key Rights for User memory (PKRU) is a 32-bit
user-accessible register. It contains two bits for each
protection key: one to write-disable (WD) access to memory
covered by the key and another to access-disable (AD).
Userspace can read/write the register with the RDPKRU and WRPKRU
instructions. But, the register is saved and restored with the
XSAVE family of instructions, which means we have to treat it
like a floating point register.
The kernel needs to write to the register if it wants to
implement execute-only memory or if it implements a system call
to change PKRU.
To do this, we need to create a 'pkru_state' buffer, read the old
contents in to it, modify it, and then tell the FPU code that
there is modified data in there so it can (possibly) move the
buffer back in to the registers.
This uses the fpu__xfeature_set_state() function that we defined
in the previous patch.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210236.0BE13217@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:35 +0000 (13:02 -0800)]
x86/fpu: Allow setting of XSAVE state
We want to modify the Protection Key rights inside the kernel, so
we need to change PKRU's contents. But, if we do a plain
'wrpkru', when we return to userspace we might do an XRSTOR and
wipe out the kernel's 'wrpkru'. So, we need to go after PKRU in
the xsave buffer.
We do this by:
1. Ensuring that we have the XSAVE registers (fpregs) in the
kernel FPU buffer (fpstate)
2. Looking up the location of a given state in the buffer
3. Filling in the stat
4. Ensuring that the hardware knows that state is present there
(basically that the 'init optimization' is not in place).
5. Copying the newly-modified state back to the registers if
necessary.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210235.5A3139BF@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:34 +0000 (13:02 -0800)]
x86/mm: Factor out LDT init from context init
The arch-specific mm_context_t is a great place to put
protection-key allocation state.
But, we need to initialize the allocation state because pkey 0 is
always "allocated". All of the runtime initialization of
mm_context_t is done in *_ldt() manipulation functions. This
renames the existing LDT functions like this:
Dave Hansen [Fri, 12 Feb 2016 21:02:32 +0000 (13:02 -0800)]
mm/core, x86/mm/pkeys: Add arch_validate_pkey()
The syscall-level code is passed a protection key and need to
return an appropriate error code if the protection key is bogus.
We will be using this in subsequent patches.
Note that this also begins a series of arch-specific calls that
we need to expose in otherwise arch-independent code. We create
a linux/pkeys.h header where we will put *all* the stubs for
these functions.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210232.774EEAAB@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:31 +0000 (13:02 -0800)]
mm/core, arch, powerpc: Pass a protection key in to calc_vm_flag_bits()
This plumbs a protection key through calc_vm_flag_bits(). We
could have done this in calc_vm_prot_bits(), but I did not feel
super strongly which way to go. It was pretty arbitrary which
one to use.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Arve Hjønnevåg <arve@android.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Chen Gang <gang.chen.5i5j@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave@sr71.net> Cc: David Airlie <airlied@linux.ie> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Geliang Tang <geliangtang@163.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Leon Romanovsky <leon@leon.nu> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Riley Andrews <riandrews@android.com> Cc: Vladimir Davydov <vdavydov@virtuozzo.com> Cc: devel@driverdev.osuosl.org Cc: linux-api@vger.kernel.org Cc: linux-arch@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/r/20160212210231.E6F1F0D6@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:29 +0000 (13:02 -0800)]
x86/mm/pkeys: Actually enable Memory Protection Keys in the CPU
This sets the bit in 'cr4' to actually enable the protection
keys feature. We also include a boot-time disable for the
feature "nopku".
Seting X86_CR4_PKE will cause the X86_FEATURE_OSPKE cpuid
bit to appear set. At this point in boot, identify_cpu()
has already run the actual CPUID instructions and populated
the "cpu features" structures. We need to go back and
re-run identify_cpu() to make sure it gets updated values.
We *could* simply re-populate the 11th word of the cpuid
data, but this is probably quick enough.
Also note that with the cpu_has() check and X86_FEATURE_PKU
present in disabled-features.h, we do not need an #ifdef
for setup_pku().
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210229.6708027C@viggo.jf.intel.com
[ Small readability edits. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:28 +0000 (13:02 -0800)]
x86/mm/pkeys: Add Kconfig prompt to existing config option
I don't have a strong opinion on whether we need this or not.
Protection Keys has relatively little code associated with it,
and it is not a heavyweight feature to keep enabled. However,
I can imagine that folks would still appreciate being able to
disable it.
Here's the option if folks want it.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210228.7E79386C@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:27 +0000 (13:02 -0800)]
x86/mm/pkeys: Dump pkey from VMA in /proc/pid/smaps
The protection key can now be just as important as read/write
permissions on a VMA. We need some debug mechanism to help
figure out if it is in play. smaps seems like a logical
place to expose it.
arch/x86/kernel/setup.c is a bit of a weirdo place to put
this code, but it already had seq_file.h and there was not
a much better existing place to put it.
We also use no #ifdef. If protection keys is .config'd out we
will effectively get the same function as if we used the weak
generic function.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Baoquan He <bhe@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Dave Young <dyoung@redhat.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Joerg Roedel <jroedel@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Laurent Dufour <ldufour@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Salter <msalter@redhat.com> Cc: Mark Williamson <mwilliamson@undo-software.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210227.4F8EB3F8@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:25 +0000 (13:02 -0800)]
x86/mm/pkeys: Dump PKRU with other kernel registers
Protection Keys never affect kernel mappings. But, they can
affect whether the kernel will fault when it touches a user
mapping. The kernel doesn't touch user mappings without some
careful choreography and these accesses don't generally result in
oopses. But, if one does, we definitely want to have PKRU
available so we can figure out if protection keys played a role.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210225.BF0D4482@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
As discussed earlier, we attempt to enforce protection keys in
software.
However, the code checks all faults to ensure that they are not
violating protection key permissions. It was assumed that all
faults are either write faults where we check PKRU[key].WD (write
disable) or read faults where we check the AD (access disable)
bit.
But, there is a third category of faults for protection keys:
instruction faults. Instruction faults never run afoul of
protection keys because they do not affect instruction fetches.
So, plumb the PF_INSTR bit down in to the
arch_vma_access_permitted() function where we do the protection
key checks.
We also add a new FAULT_FLAG_INSTRUCTION. This is because
handle_mm_fault() is not passed the architecture-specific
error_code where we keep PF_INSTR, so we need to encode the
instruction fetch information in to the arch-generic fault
flags.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210224.96928009@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:22 +0000 (13:02 -0800)]
x86/mm/pkeys: Optimize fault handling in access_error()
We might not strictly have to make modifictions to
access_error() to check the VMA here.
If we do not, we will do this:
1. app sets VMA pkey to K
2. app touches a !present page
3. do_page_fault(), allocates and maps page, sets pte.pkey=K
4. return to userspace
5. touch instruction reexecutes, but triggers PF_PK
6. do PKEY signal
What happens with this patch applied:
1. app sets VMA pkey to K
2. app touches a !present page
3. do_page_fault() notices that K is inaccessible
4. do PKEY signal
We basically skip the fault that does an allocation.
So what this lets us do is protect areas from even being
*populated* unless it is accessible according to protection
keys. That seems handy to me and makes protection keys work
more like an mprotect()'d mapping.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210222.EBB63D8C@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:21 +0000 (13:02 -0800)]
mm/core: Do not enforce PKEY permissions on remote mm access
We try to enforce protection keys in software the same way that we
do in hardware. (See long example below).
But, we only want to do this when accessing our *own* process's
memory. If GDB set PKRU[6].AD=1 (disable access to PKEY 6), then
tried to PTRACE_POKE a target process which just happened to have
some mprotect_pkey(pkey=6) memory, we do *not* want to deny the
debugger access to that memory. PKRU is fundamentally a
thread-local structure and we do not want to enforce it on access
to _another_ thread's data.
This gets especially tricky when we have workqueues or other
delayed-work mechanisms that might run in a random process's context.
We can check that we only enforce pkeys when operating on our *own* mm,
but delayed work gets performed when a random user context is active.
We might end up with a situation where a delayed-work gup fails when
running randomly under its "own" task but succeeds when running under
another process. We want to avoid that.
To avoid that, we use the new GUP flag: FOLL_REMOTE and add a
fault flag: FAULT_FLAG_REMOTE. They indicate that we are
walking an mm which is not guranteed to be the same as
current->mm and should not be subject to protection key
enforcement.
Thanks to Jerome Glisse for pointing out this scenario.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Alexey Kardashevskiy <aik@ozlabs.ru> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Boaz Harrosh <boaz@plexistor.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Chinner <dchinner@redhat.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Gibson <david@gibson.dropbear.id.au> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Dominik Dingel <dingel@linux.vnet.ibm.com> Cc: Dominik Vogt <vogt@linux.vnet.ibm.com> Cc: Eric B Munson <emunson@akamai.com> Cc: Geliang Tang <geliangtang@163.com> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jan Kara <jack@suse.cz> Cc: Jason Low <jason.low2@hp.com> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Laurent Dufour <ldufour@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Hocko <mhocko@suse.com> Cc: Mikulas Patocka <mpatocka@redhat.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Shachar Raindel <raindel@mellanox.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Xie XiuQi <xiexiuqi@huawei.com> Cc: iommu@lists.linux-foundation.org Cc: linux-arch@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org Cc: linux-s390@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:19 +0000 (13:02 -0800)]
mm/gup, x86/mm/pkeys: Check VMAs and PTEs for protection keys
Today, for normal faults and page table walks, we check the VMA
and/or PTE to ensure that it is compatible with the action. For
instance, if we get a write fault on a non-writeable VMA, we
SIGSEGV.
We try to do the same thing for protection keys. Basically, we
try to make sure that if a user does this:
mprotect(ptr, size, PROT_NONE);
*ptr = foo;
they see the same effects with protection keys when they do this:
The state to do that checking is in the VMA, but we also
sometimes have to do it on the page tables only, like when doing
a get_user_pages_fast() where we have no VMA.
We add two functions and expose them to generic code:
These are, of course, backed up in x86 arch code with checks
against the PTE or VMA's protection key.
But, there are also cases where we do not want to respect
protection keys. When we ptrace(), for instance, we do not want
to apply the tracer's PKRU permissions to the PTEs from the
process being traced.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Alexey Kardashevskiy <aik@ozlabs.ru> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Boaz Harrosh <boaz@plexistor.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave@sr71.net> Cc: David Gibson <david@gibson.dropbear.id.au> Cc: David Hildenbrand <dahi@linux.vnet.ibm.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Dominik Dingel <dingel@linux.vnet.ibm.com> Cc: Dominik Vogt <vogt@linux.vnet.ibm.com> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Low <jason.low2@hp.com> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Laurent Dufour <ldufour@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Hocko <mhocko@suse.com> Cc: Mikulas Patocka <mpatocka@redhat.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Shachar Raindel <raindel@mellanox.com> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Toshi Kani <toshi.kani@hpe.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: linux-arch@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org Cc: linux-s390@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/r/20160212210219.14D5D715@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:18 +0000 (13:02 -0800)]
x86/mm/gup: Simplify get_user_pages() PTE bit handling
The current get_user_pages() code is a wee bit more complicated
than it needs to be for pte bit checking. Currently, it establishes
a mask of required pte _PAGE_* bits and ensures that the pte it
goes after has all those bits.
This consolidates the three identical copies of this code.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210218.3A2D4045@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:15 +0000 (13:02 -0800)]
x86/mm/pkeys: Add functions to fetch PKRU
This adds the raw instruction to access PKRU as well as some
accessor functions that correctly handle when the CPU does not
support the instruction. We don't use it here, but we will use
read_pkru() in the next patch.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210215.15238D34@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:14 +0000 (13:02 -0800)]
x86/mm/pkeys: Fill in pkey field in siginfo
This fills in the new siginfo field: si_pkey to indicate to
userspace which protection key was set on the PTE that we faulted
on.
Note though that *ALL* protection key faults have to be generated
by a valid, present PTE at some point. But this code does no PTE
lookups which seeds odd. The reason is that we take advantage of
the way we generate PTEs from VMAs. All PTEs under a VMA share
some attributes. For instance, they are _all_ either PROT_READ
*OR* PROT_NONE. They also always share a protection key, so we
never have to walk the page tables; we just use the VMA.
Note that _pkey is a 64-bit value. The current hardware only
supports 4-bit protection keys. We do this because there is
_plenty_ of space in _sigfault and it is possible that future
processors would support more than 4 bits of protection keys.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210213.ABC488FA@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:12 +0000 (13:02 -0800)]
signals, pkeys: Notify userspace about protection key faults
A protection key fault is very similar to any other access error.
There must be a VMA, etc... We even want to take the same action
(SIGSEGV) that we do with a normal access fault.
However, we do need to let userspace know that something is
different. We do this the same way what we did with SEGV_BNDERR
with Memory Protection eXtensions (MPX): define a new SEGV code:
SEGV_PKUERR.
We add a siginfo field: si_pkey that reveals to userspace which
protection key was set on the PTE that we faulted on. There is
no other easy way for userspace to figure this out. They could
parse smaps but that would be a bit cruel.
We share space with in siginfo with _addr_bnd. #BR faults from
MPX are completely separate from page faults (#PF) that trigger
from protection key violations, so we never need both at the same
time.
Note that _pkey is a 64-bit value. The current hardware only
supports 4-bit protection keys. We do this because there is
_plenty_ of space in _sigfault and it is possible that future
processors would support more than 4 bits of protection keys.
The x86 code to actually fill in the siginfo is in the next
patch.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Amanieu d'Antras <amanieu@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Richard Weinberger <richard@nod.at> Cc: Rik van Riel <riel@redhat.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: linux-arch@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210212.3A9B83AC@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:11 +0000 (13:02 -0800)]
x86/mm/pkeys: Pass VMA down in to fault signal generation code
During a page fault, we look up the VMA to ensure that the fault
is in a region with a valid mapping. But, in the top-level page
fault code we don't need the VMA for much else. Once we have
decided that an access is bad, we are going to send a signal no
matter what and do not need the VMA any more. So we do not pass
it down in to the signal generation code.
But, for protection keys, we need the VMA. It tells us *which*
protection key we violated if we get a PF_PK. So, we need to
pass the VMA down and fill in siginfo->si_pkey.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210211.AD3B36A3@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
and the ptes get created right from things we pull out
of ->vm_page_prot. So it is very convenient if we can
store the protection key in flags and vm_page_prot, just
like the existing permission bits (_PAGE_RW/PRESENT). It
greatly reduces the amount of plumbing and arch-specific
hacking we have to do in generic code.
This also takes the new PROT_PKEY{0,1,2,3} flags and
turns *those* in to VM_ flags for vma->vm_flags.
The protection key values are stored in 4 places:
1. "prot" argument to system calls
2. vma->vm_flags, filled from the mmap "prot"
3. vma->vm_page prot, filled from vma->vm_flags
4. the PTE itself.
The pseudocode for these for steps are as follows:
Dave Hansen [Fri, 12 Feb 2016 21:02:08 +0000 (13:02 -0800)]
mm/core, x86/mm/pkeys: Store protection bits in high VMA flags
vma->vm_flags is an 'unsigned long', so has space for 32 flags
on 32-bit architectures. The high 32 bits are unused on 64-bit
platforms. We've steered away from using the unused high VMA
bits for things because we would have difficulty supporting it
on 32-bit.
Protection Keys are not available in 32-bit mode, so there is
no concern about supporting this feature in 32-bit mode or on
32-bit CPUs.
This patch carves out 4 bits from the high half of
vma->vm_flags and allows architectures to set config option
to make them available.
Sparse complains about these constants unless we explicitly
call them "UL".
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jan Kara <jack@suse.cz> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Valentin Rothberg <valentinrothberg@gmail.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Xie XiuQi <xiexiuqi@huawei.com> Cc: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210208.81AF00D5@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:05 +0000 (13:02 -0800)]
x86/mm/pkeys: Add PTE bits for storing protection key
Previous documentation has referred to these 4 bits as "ignored".
That means that software could have made use of them. But, as
far as I know, the kernel never used them.
They are still ignored when protection keys is not enabled, so
they could theoretically still get used for software purposes.
We also implement "empty" versions so that code that references
to them can be optimized away by the compiler when the config
option is not enabled.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210205.81E33ED6@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:04 +0000 (13:02 -0800)]
x86/fpu, x86/mm/pkeys: Add PKRU xsave fields and data structures
The protection keys register (PKRU) is saved and restored using
xsave. Define the data structure that we will use to access it
inside the xsave buffer.
Note that we also have to widen the printk of the xsave feature
masks since this is feature 0x200 and we only did two characters
before.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210204.56DF8F7B@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:01 +0000 (13:02 -0800)]
x86/cpufeature, x86/mm/pkeys: Add protection keys related CPUID definitions
There are two CPUID bits for protection keys. One is for whether
the CPU contains the feature, and the other will appear set once
the OS enables protection keys. Specifically:
Bit 04: OSPKE. If 1, OS has set CR4.PKE to enable
Protection keys (and the RDPKRU/WRPKRU instructions)
This is because userspace can not see CR4 contents, but it can
see CPUID contents.
X86_FEATURE_PKU is referred to as "PKU" in the hardware documentation:
CPUID.(EAX=07H,ECX=0H):ECX.PKU [bit 3]
X86_FEATURE_OSPKE is "OSPKU":
CPUID.(EAX=07H,ECX=0H):ECX.OSPKE [bit 4]
These are the first CPU features which need to look at the
ECX word in CPUID leaf 0x7, so this patch also includes
fetching that word in to the cpuinfo->x86_capability[] array.
Add it to the disabled-features mask when its config option is
off. Even though we are not using it here, we also extend the
REQUIRED_MASK_BIT_SET() macro to keep it mirroring the
DISABLED_MASK_BIT_SET() version.
This means that in almost all code, you should use:
cpu_has(c, X86_FEATURE_PKU)
and *not* the CONFIG option.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210201.7714C250@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:02:00 +0000 (13:02 -0800)]
x86/mm/pkeys: Add Kconfig option
I don't have a strong opinion on whether we need a Kconfig prompt
or not. Protection Keys has relatively little code associated
with it, and it is not a heavyweight feature to keep enabled.
However, I can imagine that folks would still appreciate being
able to disable it.
Note that, with disabled-features.h, the checks in the code
for protection keys are always the same:
cpu_has(c, X86_FEATURE_PKU)
With the config option disabled, this essentially turns into an
We will hide the prompt for now.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210200.DB7055E8@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:01:58 +0000 (13:01 -0800)]
x86/fpu: Add placeholder for 'Processor Trace' XSAVE state
There is an XSAVE state component for Intel Processor Trace (PT).
But, we do not currently use it.
We add a placeholder in the code for it so it is not a mystery and
also so we do not need an explicit enum initialization for Protection
Keys in a moment.
Why don't we use it?
We might end up using this at _some_ point in the future. But,
this is a "system" state which requires using the currently
unsupported XSAVES feature. Unlike all the other XSAVE states,
PT state is also not directly tied to a thread. You might
context-switch between threads, but not want to change any of the
PT state. Or, you might switch between threads, and *do* want to
change PT state, all depending on what is being traced.
We currently just manually set some MSRs to do this PT context
switching, and it is unclear whether replacing our direct MSR use
with XSAVE will be a net win or loss, both in code complexity and
performance.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: fenghua.yu@intel.com Cc: linux-mm@kvack.org Cc: yu-cheng.yu@intel.com Link: http://lkml.kernel.org/r/20160212210158.5E4BCAE2@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:01:56 +0000 (13:01 -0800)]
mm/gup: Switch all callers of get_user_pages() to not pass tsk/mm
We will soon modify the vanilla get_user_pages() so it can no
longer be used on mm/tasks other than 'current/current->mm',
which is by far the most common way it is called. For now,
we allow the old-style calls, but warn when they are used.
(implemented in previous patch)
Dave Hansen [Fri, 12 Feb 2016 21:01:55 +0000 (13:01 -0800)]
mm/gup: Overload get_user_pages() functions
The concept here was a suggestion from Ingo. The implementation
horrors are all mine.
This allows get_user_pages(), get_user_pages_unlocked(), and
get_user_pages_locked() to be called with or without the
leading tsk/mm arguments. We will give a compile-time warning
about the old style being __deprecated and we will also
WARN_ON() if the non-remote version is used for a remote-style
access.
Doing this, folks will get nice warnings and will not break the
build. This should be nice for -next and will hopefully let
developers fix up their own code instead of maintainers needing
to do it at merge time.
The way we do this is hideous. It uses the __VA_ARGS__ macro
functionality to call different functions based on the number
of arguments passed to the macro.
There's an additional hack to ensure that our EXPORT_SYMBOL()
of the deprecated symbols doesn't trigger a warning.
We should be able to remove this mess as soon as -rc1 hits in
the release after this is merged.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Alexander Kuleshov <kuleshovmail@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave@sr71.net> Cc: Dominik Dingel <dingel@linux.vnet.ibm.com> Cc: Geliang Tang <geliangtang@163.com> Cc: Jan Kara <jack@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Leon Romanovsky <leon@leon.nu> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Mateusz Guzik <mguzik@redhat.com> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vladimir Davydov <vdavydov@virtuozzo.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Xie XiuQi <xiexiuqi@huawei.com> Cc: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210155.73222EE1@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Fri, 12 Feb 2016 21:01:54 +0000 (13:01 -0800)]
mm/gup: Introduce get_user_pages_remote()
For protection keys, we need to understand whether protections
should be enforced in software or not. In general, we enforce
protections when working on our own task, but not when on others.
We call these "current" and "remote" operations.
This patch introduces a new get_user_pages() variant:
get_user_pages_remote()
Which is a replacement for when get_user_pages() is called on
non-current tsk/mm.
We also introduce a new gup flag: FOLL_REMOTE which can be used
for the "__" gup variants to get this new behavior.
The uprobes is_trap_at_addr() location holds mmap_sem and
calls get_user_pages(current->mm) on an instruction address. This
makes it a pretty unique gup caller. Being an instruction access
and also really originating from the kernel (vs. the app), I opted
to consider this a 'remote' access where protection keys will not
be enforced.
Without protection keys, this patch should not change any behavior.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: jack@suse.cz Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210154.3F0E51EA@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Borislav Petkov [Mon, 15 Feb 2016 23:19:18 +0000 (00:19 +0100)]
x86/cpufeature: Speed up cpu_feature_enabled()
When GCC cannot do constant folding for this macro, it falls back to
cpu_has(). But static_cpu_has() is optimal and it works at all times
now. So use it and speedup the fallback case.
Before we had this:
mov 0x99d674(%rip),%rdx # ffffffff81b0d9f4 <boot_cpu_data+0x34>
shr $0x2e,%rdx
and $0x1,%edx
jne ffffffff811704e9 <do_munmap+0x3f9>
Simon Horman [Mon, 15 Feb 2016 01:49:47 +0000 (10:49 +0900)]
MAINTAINERS: Update mailing list for Renesas ARM64 SoC Development
Update the mailing list used for development of support for ARM64
Renesas SoCs.
This is a follow-up for a similar change for other Renesas SoCs and
drivers uses by Renesas SoCs. The ARM64 SoC entry was not updated in
that patch as it was not yet present in mainline.
The motivation for the mailing list update is that Renesas SoCs are now
much wider than the SH architecture and there is some desire from some
for the linux-sh list to refocus on discussion of the work on the SH
architecture.
Acked-by: Magnus Damm <damm@opensource.se> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Mon, 15 Feb 2016 02:34:12 +0000 (18:34 -0800)]
Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
Pull i915 drm fixes from Dave Airlie:
"Jani sent a bunch of i915 display fixes as my weekend started, but
hopefully you can fit them in"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm/i915: fix error path in intel_setup_gmbus()
drm/i915/skl: Fix typo in DPLL_CFGCR1 definition
drm/i915/skl: Don't skip mst encoders in skl_ddi_pll_select()
drm/i915: Pretend cursor is always on for ILK-style WM calculations (v2)
drm/i915/dp: reduce missing TPS3 support errors to debug logging
drm/i915/dp: abstract training pattern selection
drm/i915/dsi: skip gpio element execution when not supported
drm/i915/dsi: don't pass arbitrary data to sideband
drm/i915/dsi: defend gpio table against out of bounds access
drm/i915/bxt: Don't save/restore eDP panel power during suspend (v3)
drm/i915: Allow i915_gem_object_get_page() on userptr as well
Dave Airlie [Sun, 14 Feb 2016 20:54:50 +0000 (06:54 +1000)]
Merge tag 'drm-intel-fixes-2016-02-12' of git://anongit.freedesktop.org/drm-intel into drm-fixes
i915 display fixes mostly.
* tag 'drm-intel-fixes-2016-02-12' of git://anongit.freedesktop.org/drm-intel:
drm/i915: fix error path in intel_setup_gmbus()
drm/i915/skl: Fix typo in DPLL_CFGCR1 definition
drm/i915/skl: Don't skip mst encoders in skl_ddi_pll_select()
drm/i915: Pretend cursor is always on for ILK-style WM calculations (v2)
drm/i915/dp: reduce missing TPS3 support errors to debug logging
drm/i915/dp: abstract training pattern selection
drm/i915/dsi: skip gpio element execution when not supported
drm/i915/dsi: don't pass arbitrary data to sideband
drm/i915/dsi: defend gpio table against out of bounds access
drm/i915/bxt: Don't save/restore eDP panel power during suspend (v3)
drm/i915: Allow i915_gem_object_get_page() on userptr as well
Linus Torvalds [Sun, 14 Feb 2016 20:47:45 +0000 (12:47 -0800)]
Merge tag 'char-misc-4.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver fixes from Greg KH:
"Here are 3 fixes for some reported issues. Two nvmem driver fixes,
and one mei fix. All have been in linux-next just fine"
* tag 'char-misc-4.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
nvmem: qfprom: Specify LE device endianness
nvmem: core: return error for non word aligned access
mei: validate request value in client notify request ioctl
Linus Torvalds [Sun, 14 Feb 2016 20:34:53 +0000 (12:34 -0800)]
Merge tag 'driver-core-4.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core fix from Greg KH:
"Here is one driver core, well klist, fix for 4.5-rc4.
It fixes a problem found in the scsi device list traversal that
probably also could be triggered by other subsystems.
The fix has been in linux-next for a while with no reported problems"
* tag 'driver-core-4.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
klist: fix starting point removed bug in klist iterators
Linus Torvalds [Sun, 14 Feb 2016 20:29:59 +0000 (12:29 -0800)]
Merge tag 'tty-4.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial fixes from Greg KH:
"Here are a number of small tty and serial driver fixes for 4.5-rc4
that resolve some reported issues.
One of them got reverted as it wasn't correct based on testing, and
all have been in linux-next for a while"
* tag 'tty-4.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
Revert "8250: uniphier: allow modular build with 8250 console"
pty: make sure super_block is still valid in final /dev/tty close
pty: fix possible use after free of tty->driver_data
tty: Add support for PCIe WCH382 2S multi-IO card
serial/omap: mark wait_for_xmitr as __maybe_unused
serial: omap: Prevent DoS using unprivileged ioctl(TIOCSRS485)
8250: uniphier: allow modular build with 8250 console
tty: Drop krefs for interrupted tty lock
Linus Torvalds [Sun, 14 Feb 2016 20:24:28 +0000 (12:24 -0800)]
Merge tag 'usb-4.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull PHY fixes from Greg KH:
"Here are a couple of PHY driver fixes for 4.5-rc4.
A few small phy issues. All have been in linux-next with no reported
issues"
* tag 'usb-4.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
phy: twl4030-usb: Fix unbalanced pm_runtime_enable on module reload
phy: twl4030-usb: Relase usb phy on unload
phy: core: fix wrong err handle for phy_power_on
phy: Restrict phy-hi6220-usb to HiSilicon arm64
Linus Torvalds [Sun, 14 Feb 2016 20:07:55 +0000 (12:07 -0800)]
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf tooling fixes from Thomas Gleixner:
"Another round of fixes for the perf tooling side:
- Prevent a NULL pointer dereference in tracepoint error handling
- Fix a thread handling bug in the intel_pt error handling code
- Search both .eh_frame and .debug_frame sections as toolchains seem
to have random choices of storing the CFI information
- Fix the perf state interval output values, which got broken when
fixing the overall output"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf stat: Fix interval output values
perf probe: Search both .eh_frame and .debug_frame sections for probe location
perf tools: Fix thread lifetime related segfaut in intel_pt
perf tools: tracepoint_error() can receive e=NULL, robustify it
Linus Torvalds [Sun, 14 Feb 2016 20:02:05 +0000 (12:02 -0800)]
Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull lockdep fix from Thomas Gleixner:
"A single fix for the stack trace caching logic in lockdep, where the
duplicate avoidance managed to store no back trace at all"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/lockdep: Fix stack trace caching logic
Linus Torvalds [Sun, 14 Feb 2016 19:49:30 +0000 (11:49 -0800)]
Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irqchip fixes from Thomas Gleixner:
"Another set of ARM SoC related irqchip fixes:
- Plug a memory leak in gicv3-its
- Limit features to the root gic interrupt controller
- Add a missing barrier in the gic-v3 IAR access
- Another compile test fix for sun4i"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/gic-v3: Make sure read from ICC_IAR1_EL1 is visible on redestributor
irqchip/gic: Only set the EOImodeNS bit for the root controller
irqchip/gic: Only populate set_affinity for the root controller
irqchip/gicv3-its: Fix memory leak in its_free_tables()
irqchip/sun4i: Fix compilation outside of arch/arm
Linus Torvalds [Sun, 14 Feb 2016 18:50:26 +0000 (10:50 -0800)]
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
"Two small fixlets for x86:
- Prevent a KASAN false positive in thread_saved_pc()
- Fix a 32-bit truncation problem in the x86 numa code"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm/numa: Fix 32-bit memblock range truncation bug on 32-bit NUMA kernels
x86: Fix KASAN false positives in thread_saved_pc()
Linus Torvalds [Sun, 14 Feb 2016 18:49:01 +0000 (10:49 -0800)]
Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS fixes from Ralf Baechle:
"Here's the first round of MIPS fixes after the merge window:
- Detect Octeon III's PCI correctly.
- Fix return value of the MT7620 probing function.
- Wire up the copy_file_range syscall.
- Fix 64k page support on 32 bit kernels.
- Fix the early Coherency Manager probe.
- Allow only hardware-supported page sizes to be selected for R6000.
- Fix corner cases for the RDHWR nstruction emulation on old hardware.
- Fix FPU handling corner cases.
- Remove stale entry for BCM33xx from the MAINTAINERS file.
- 32 and 64 bit ELF headers are different, handle them correctly"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
mips: Differentiate between 32 and 64 bit ELF header
MIPS: Octeon: Update OCTEON_FEATURE_PCIE for Octeon III
MIPS: pci-mt7620: Fix return value check in mt7620_pci_probe()
MIPS: Fix early CM probing
MIPS: Wire up copy_file_range syscall.
MIPS: Fix 64k page support for 32 bit kernels.
MIPS: R6000: Don't allow 64k pages for R6000.
MIPS: traps.c: Correct microMIPS RDHWR emulation
MIPS: traps.c: Don't emulate RDHWR in the CpU #0 exception handler
MAINTAINERS: Remove stale entry for BCM33xx chips
MIPS: Fix FPU disable with preemption
MIPS: Properly disable FPU in start_thread()
MIPS: Fix buffer overflow in syscall_get_arguments()
Linus Torvalds [Sun, 14 Feb 2016 18:46:47 +0000 (10:46 -0800)]
Merge branch 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm
Pull ARM fixes from Russell King:
"A couple of ARM fixes from Linus for the ICST clock generator code"
[ "Linus" here is Linus Walleij. Name-stealer.
Linus "there can be only one" Torvalds ]
* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
ARM: 8519/1: ICST: try other dividends than 1
ARM: 8517/1: ICST: avoid arithmetic overflow in icst_hz()
Linus Torvalds [Sun, 14 Feb 2016 18:40:21 +0000 (10:40 -0800)]
Merge branch 'component' of git://ftp.arm.linux.org.uk/~rmk/linux-arm
Pull component helper fixes from Russell King:
"A few fixes for problems people have encountered with the recent
update to the component helpers"
* 'component' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
component: remove device from master match list on failed add
component: Detach components when deleting master struct
component: fix crash on x86_64 with hda audio drivers
Borislav Petkov [Wed, 10 Feb 2016 14:51:16 +0000 (15:51 +0100)]
x86/mm: Fix INVPCID asm constraint
So we want to specify the dependency on both @pcid and @addr so that the
compiler doesn't reorder accesses to them *before* the TLB flush. But
for that to work, we need to express this properly in the inline asm and
deref the whole desc array, not the pointer to it. See clwb() for an
example.
This fixes the build error on 32-bit:
arch/x86/include/asm/tlbflush.h: In function ‘__invpcid’:
arch/x86/include/asm/tlbflush.h:26:18: error: memory input 0 is not directly addressable
which gcc4.7 caught but 5.x didn't. Which is strange. :-\
Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Michael Matz <matz@suse.de> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: linux-mm@kvack.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma:
IB/mlx5: Fix RC transport send queue overhead computation
IB/ipoib: fix for rare multicast join race condition
IB/core: Fix reading capability mask of the port info class
net/mlx4: fix some error handling in mlx4_multi_func_init()
Pull SCSI target fixes from Nicholas Bellinger:
"This includes the long awaited series to address a set of bugs around
active I/O remote-port LUN_RESET, as well as properly handling this
same case with concurrent fabric driver session disconnect ->
reconnect.
Note this set of LUN_RESET bug-fixes has been surviving extended
testing on both v4.5-rc1 and v3.14.y code over the last weeks, and is
CC'ed for stable as it's something folks using multiple ESX connected
hosts with slow backends can certainly trigger.
- Fix TMR abort interaction and AIO type TMR response in qla2xxx
target (Quinn Tran + Swapnil Nagle)
- Fix >= v3.17 stale descriptor pointer regression in qla2xxx target
(Quinn Tran)
- Fix >= v4.5-rc1 return regression with unmap_zeros_data_store new
configfs store handler (nab)
- Add CPU affinity flag + convert qla2xxx to use bit (Quinn + HCH +
Bart)"
* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
qla2xxx: use TARGET_SCF_USE_CPUID flag to indiate CPU Affinity
target/transport: add flag to indicate CPU Affinity is observed
target: Fix incorrect unmap_zeroes_data_store return
qla2xxx: Use ATIO type to send correct tmr response
qla2xxx: Fix stale pointer access.
target/user: Fix cast from pointer to phys_addr_t
target: Drop legacy se_cmd->task_stop_comp + REQUEST_STOP usage
target: Fix race with SCF_SEND_DELAYED_TAS handling
target: Fix remote-port TMR ABORT + se_cmd fabric stop
target: Fix TAS handling for multi-session se_node_acls
target: Fix LUN_RESET active TMR descriptor handling
target: Fix LUN_RESET active I/O handling for ACK_KREF
qla2xxx: Fix TMR ABORT interaction issue between qla2xxx and TCM
qla2xxx: Fix warning reported by static checker
target: Fix WRITE_SAME/DISCARD conversion to linux 512b sectors
Linus Torvalds [Sat, 13 Feb 2016 21:05:56 +0000 (13:05 -0800)]
Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal
Pull thermal management fixes from Eduardo Valentin:
"Specifics in this pull request:
- Compilation fixes on SPEAR, and U8500 thermal drivers.
- RCAR thermal driver now recognizes OF-thermal based thermal zones.
- Small code rework on OF-thermal.
- These change have been CI tested using KernelCI bot [1,2]. \o/
I am taking over on Rui's behalf while he is out. Happy New Chinese
Year!
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal:
thermal: cpu_cooling: fix out of bounds access in time_in_idle
thermal: allow u8500-thermal driver to be a module
thermal: allow spear-thermal driver to be a module
thermal: spear: use __maybe_unused for PM functions
thermal: rcar: enable to use thermal-zone on DT
thermal: of: use for_each_available_child_of_node for child iterator
Linus Torvalds [Sat, 13 Feb 2016 16:18:21 +0000 (08:18 -0800)]
Merge tag 'arc-4.5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
Pull ARC fixes from Vineet Gupta:
"I've been sitting on some of these fixes for a while.
- Corner case of returning to delay slot from interrupt
- Changing default interrupt prioiry level
- Kconfig'ize support for super pages
- Other minor fixes"
* tag 'arc-4.5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
ARC: mm: Introduce explicit super page size support
ARCv2: intc: Allow interruption by lowest priority interrupt
ARCv2: Check for LL-SC livelock only if LLSC is enabled
ARC: shrink cpuinfo by not saving full timer BCR
ARCv2: clocksource: Rename GRTC -> GFRC ...
ARCv2: STAR 9000950267: Handle return from intr to Delay Slot #2
Andrey Konovalov [Sat, 13 Feb 2016 08:08:06 +0000 (11:08 +0300)]
ALSA: usb-audio: avoid freeing umidi object twice
The 'umidi' object will be free'd on the error path by snd_usbmidi_free()
when tearing down the rawmidi interface. So we shouldn't try to free it
in snd_usbmidi_create() after having registered the rawmidi interface.
Linus Torvalds [Fri, 12 Feb 2016 23:31:22 +0000 (15:31 -0800)]
Merge tag 'pci-v4.5-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI fixes from Bjorn Helgaas:
"These are some Renesas binding updates for PCI host controllers, a
Broadcom fix for a regression we added in v4.5-rc1, and a fix for an
AER use-after-free problem that can cause memory corruption.
Summary:
AER:
Flush workqueue on device remove to avoid use-after-free (Sebastian Andrzej Siewior)
Renesas R-Car host bridge driver:
Add gen2 device tree support for r8a7793 (Simon Horman)
Add device tree support for r8a7793 (Simon Horman)"
* tag 'pci-v4.5-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
PCI: rcar: Add device tree support for r8a7793
PCI: rcar: Add gen2 device tree support for r8a7793
PCI: iproc: Allow multiple devices except on PAXC
PCI/AER: Flush workqueue on device remove to avoid use-after-free
Linus Torvalds [Fri, 12 Feb 2016 21:12:27 +0000 (13:12 -0800)]
Merge branch 'akpm'(patches from Andrew)
Merge fixes from Andrew Morton:
"10 fixes"
The lockdep hlist conversion is in the locking tree too, waiting for the
next merge window. Andrew thought it should go in now. I'll take it,
since it fixes a real problem and looks trivially correct (famous last
words).
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
arch/x86/Kconfig: CONFIG_X86_UV should depend on CONFIG_EFI
mm: fix pfn_t vs highmem
kernel/locking/lockdep.c: convert hash tables to hlists
mm,thp: fix spellos in describing __HAVE_ARCH_FLUSH_PMD_TLB_RANGE
mm,thp: khugepaged: call pte flush at the time of collapse
mm/backing-dev.c: fix error path in wb_init()
mm, dax: check for pmd_none() after split_huge_pmd()
vsprintf: kptr_restrict is okay in IRQ when 2
mm: fix filemap.c kernel doc warning
ubsan: cosmetic fix to Kconfig text
Leon Romanovsky [Thu, 11 Feb 2016 19:09:57 +0000 (21:09 +0200)]
IB/mlx5: Fix RC transport send queue overhead computation
Fix the RC QPs send queue overhead computation to take into account
two additional segments in the WQE which are needed for registration
operations.
The ATOMIC and UMR segments can't coexist together, so chose maximum out
of them.
The commit 9e65dc371b5c ("IB/mlx5: Fix RC transport send queue overhead
computation") was intended to update RC transport as commit messages
states, but added the code to UC transport.
Fixes: 9e65dc371b5c ("IB/mlx5: Fix RC transport send queue overhead computation") Signed-off-by: Kamal Heib <kamalh@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Reviewed-by: Sagi Grimberg <sagig@mellanox.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
Alex Estrin [Thu, 11 Feb 2016 21:30:51 +0000 (16:30 -0500)]
IB/ipoib: fix for rare multicast join race condition
A narrow window for race condition still exist between
multicast join thread and *dev_flush workers.
A kernel crash caused by prolong erratic link state changes
was observed (most likely a faulty cabling):
[167275.656270] BUG: unable to handle kernel NULL pointer dereference at 0000000000000020
[167275.665973] IP: [<ffffffffa05f8f2e>] ipoib_mcast_join+0xae/0x1d0 [ib_ipoib]
[167275.674443] PGD 0
[167275.677373] Oops: 0000 [#1] SMP
...
[167275.977530] Call Trace:
[167275.982225] [<ffffffffa05f92f0>] ? ipoib_mcast_free+0x200/0x200 [ib_ipoib]
[167275.992024] [<ffffffffa05fa1b7>] ipoib_mcast_join_task+0x2a7/0x490
[ib_ipoib]
[167276.002149] [<ffffffff8109d5fb>] process_one_work+0x17b/0x470
[167276.010754] [<ffffffff8109e3cb>] worker_thread+0x11b/0x400
[167276.019088] [<ffffffff8109e2b0>] ? rescuer_thread+0x400/0x400
[167276.027737] [<ffffffff810a5aef>] kthread+0xcf/0xe0
Here was a hit spot:
ipoib_mcast_join() {
..............
rec.qkey = priv->broadcast->mcmember.qkey;
^^^^^^^
.....
}
Proposed patch should prevent multicast join task to continue
if link state change is detected.
Signed-off-by: Alex Estrin <alex.estrin@intel.com>
Changes from v4:
- as suggested by Doug Ledford, optimized spinlock usage,
i.e. ipoib_mcast_join() is called with lock held.
Changes from v3:
- sync with priv->lock before flag check.
Chages from v2:
- Move check for OPER_UP flag state to mcast_join() to
ensure no event worker is in progress.
- minor style fixes.
Changes from v1:
- No need to lock again if error detected. Signed-off-by: Doug Ledford <dledford@redhat.com>
Linus Torvalds [Fri, 12 Feb 2016 17:42:05 +0000 (09:42 -0800)]
Merge tag 'sound-4.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"In this rc, we've got more volume than previous rc, unsurprisingly;
the majority of updates in ASoC are about Intel drivers, and another
major changes are the continued plumbing of ALSA timer bugs revealed
by syzkaller fuzzer. Hopefully both settle down now.
Other than that, HD-audio received a couple of code fixes as well as
the usual quirks, and various small fixes are found for FireWire
devices, ASoC codecs and drivers"
* tag 'sound-4.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (50 commits)
ASoC: arizona: fref must be limited in pseudo-fractional mode
ASoC: sigmadsp: Fix missleading return value
ALSA: timer: Fix race at concurrent reads
ALSA: firewire-digi00x: Drop bogus const type qualifier on dot_scrt()
ALSA: hda - Fix bad dereference of jack object
ALSA: timer: Fix race between stop and interrupt
ALSA: timer: Fix wrong instance passed to slave callbacks
ASoC: Intel: Add module tags for common match module
ASoC: Intel: Load the atom DPCM driver only
ASoC: Intel: Create independent acpi match module
ASoC: Intel: Revert "ASoC: Intel: fix ACPI probe regression with Atom DPCM driver"
ALSA: dummy: Implement timer backend switching more safely
ALSA: hda - Fix speaker output from VAIO AiO machines
Revert "ALSA: hda - Fix noise on Gigabyte Z170X mobo"
ALSA: firewire-tascam: remove needless member for control and status message
ALSA: firewire-tascam: remove a flag for controller
ALSA: firewire-tascam: add support for FW-1804
ALSA: firewire-tascam: fix NULL pointer dereference when model identification fails
ALSA: hda - Fix static checker warning in patch_hdmi.c
ASoC: Intel: Skylake: Remove autosuspend delay
...
Linus Torvalds [Fri, 12 Feb 2016 17:39:34 +0000 (09:39 -0800)]
Merge tag 'fbdev-fixes-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tomba/linux
Pull fbdev fixes from Tomi Valkeinen:
- fix omap2plus_defconfig to enable omapfb as it was in v4.4
- ocfb: fix timings for margins
- s6e8ax0, da8xx-fb: fix compile warnings
- mmp: fix build failure caused by bad printk parameters
- imxfb: fix clock issue which kept the display off
* tag 'fbdev-fixes-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tomba/linux:
video: fbdev: imxfb: Provide a reset mechanism
fbdev: mmp: print IRQ resource using %pR format string
fbdev: da8xx-fb: remove incorrect type cast
fbdev: s6e8ax0: avoid unused function warnings
ocfb: fix tgdel and tvdel timing parameters
ARM: omap2plus_defconfig: update display configs
Linus Torvalds [Fri, 12 Feb 2016 17:32:37 +0000 (09:32 -0800)]
Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"A set of seven fixes:
Two regressions in the new hisi_sas arm driver, a blacklist entry for
the marvell console which was causing a reset cascade without it, a
race fix in the WRITE_SAME/DISCARD routines, a retry fix for the rdac
driver, without which, it would prematurely return EIO and a couple of
fixes for the hyper-v storvsc driver"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
block/sd: Return -EREMOTEIO when WRITE SAME and DISCARD are disabled
SCSI: Add Marvell Console to VPD blacklist
scsi_dh_rdac: always retry MODE SELECT on command lock violation
storvsc: Use the specified target ID in device lookup
storvsc: Install the storvsc specific timeout handler for FC devices
hisi_sas: fix v1 hw check for slot error
hisi_sas: add dependency for HAS_IOMEM
Linus Torvalds [Fri, 12 Feb 2016 17:27:31 +0000 (09:27 -0800)]
Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
Pull drm amd fixes from Dave Airlie:
"Been pretty quiet.
This is an amdgpu fixes pull from AMD, a bunch of powerplay stability
fixes, race fix, hibernate fix, and a possible circular locking fix"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (21 commits)
drm/amdgpu: fix issue with overlapping userptrs
drm/radeon: hold reference to fences in radeon_sa_bo_new
drm/amdgpu: remove unnecessary forward declaration
drm/amdgpu: hold reference to fences in amdgpu_sa_bo_new (v2)
drm/amdgpu: fix s4 resume
drm/amdgpu/cz: plumb pg flags through to powerplay
drm/amdgpu/tonga: plumb pg flags through to powerplay
drma/dmgpu: move cg and pg flags into shared headers
drm/amdgpu: remove unused cg defines
drm/amdgpu: add a cgs interface to fetch cg and pg flags
drm/amd/powerplay/tonga: disable vce pg
drm/amd/powerplay/tonga: disable uvd pg
drm/amd/powerplay/cz: disable vce pg
drm/amd/powerplay/cz: disable uvd pg
drm/amdgpu: be consistent with uvd cg flags
drm/amdgpu: clean up vce pg flags for cz/st
drm/amdgpu: handle vce pg flags properly
drm/amdgpu: handle uvd pg flags properly
drm/amdgpu/dpm/ci: switch over to the common pcie caps interface
drm/amdgpu/cik: don't mess with aspm if gpu is root bus
...
Linus Torvalds [Fri, 12 Feb 2016 17:21:28 +0000 (09:21 -0800)]
Merge branch 'for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
"This has a few fixes from Filipe, along with a readdir fix from Dave
that we've been testing for some time"
* 'for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: properly set the termination value of ctx->pos in readdir
Btrfs: fix hang on extent buffer lock caused by the inode_paths ioctl
Btrfs: remove no longer used function extent_read_full_page_nolock()
Btrfs: fix page reading in extent_same ioctl leading to csum errors
Btrfs: fix invalid page accesses in extent_same (dedup) ioctl
Linus Torvalds [Fri, 12 Feb 2016 17:17:03 +0000 (09:17 -0800)]
Merge tag 'xfs-fixes-for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs
Pull xfs fix from Dve Chinner:
"This contains a fix for an endian conversion issue in new CRC
validation in log recovery that was discovered on a ppc64 platform"
* tag 'xfs-fixes-for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs:
xfs: fix endianness error when checking log block crc on big endian platforms
Takashi Iwai [Fri, 12 Feb 2016 08:48:51 +0000 (09:48 +0100)]
Merge tag 'asoc-fix-v4.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Fixes for v4.5
A rather large batch of fixes here, almost all in the Intel driver.
The changes that got merged in this merge window for Skylake were rather
large and as well as issues that you'd expect in a large block of new
code there were some problems created for older processors which needed
fixing up. Things are largely settling down now hopefully.
Ryan Ware [Thu, 11 Feb 2016 23:58:44 +0000 (15:58 -0800)]
EVM: Use crypto_memneq() for digest comparisons
This patch fixes vulnerability CVE-2016-2085. The problem exists
because the vm_verify_hmac() function includes a use of memcmp().
Unfortunately, this allows timing side channel attacks; specifically
a MAC forgery complexity drop from 2^128 to 2^12. This patch changes
the memcmp() to the cryptographically safe crypto_memneq().
Reported-by: Xiaofei Rex Guo <xiaofei.rex.guo@intel.com> Signed-off-by: Ryan Ware <ware@linux.intel.com> Cc: stable@vger.kernel.org Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
Vineet Gupta [Wed, 10 Feb 2016 01:22:07 +0000 (06:52 +0530)]
ARC: mm: Introduce explicit super page size support
MMUv4 supports 2 concurrent page sizes: Normal and Super [4K to 16M]
So far Linux supported a single super page size for a given Normal page,
depending on the software page walking address split.
e.g. we had 11:8:13 address split for 8K page, which meant super page
was 2 ^(8+13) = 2M (given that THP size has to be PMD_SHIFT)
Now we turn this around, by allowing multiple Super Pages in Kconfig
(currently 2M and 16M only) and forcing page walker address split to
PGDIR_SHIFT and PAGE_SHIFT
For configs without Super page, things are same as before and
PGDIR_SHIFT can be hacked to get non default address split
The motivation for this change is a customer who needs 16M super page
and a 8K Normal page combo.
Dan Williams [Fri, 12 Feb 2016 00:13:17 +0000 (16:13 -0800)]
mm: fix pfn_t vs highmem
The pfn_t type uses an unsigned long to store a pfn + flags value. On a
64-bit platform the upper 12 bits of an unsigned long are never used for
storing the value of a pfn. However, this is not true on highmem
platforms, all 32-bits of a pfn value are used to address a 44-bit
physical address space. A pfn_t needs to store a 64-bit value.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=112211 Fixes: 01c8f1c44b83 ("mm, dax, gpu: convert vm_insert_mixed to pfn_t") Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reported-by: Stuart Foster <smf.linux@ntlworld.com> Reported-by: Julian Margetson <runaway@candw.ms> Tested-by: Julian Margetson <runaway@candw.ms> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrew Morton [Fri, 12 Feb 2016 00:13:14 +0000 (16:13 -0800)]
kernel/locking/lockdep.c: convert hash tables to hlists
Mike said:
: CONFIG_UBSAN_ALIGNMENT breaks x86-64 kernel with lockdep enabled, i. e
: kernel with CONFIG_UBSAN_ALIGNMENT fails to load without even any error
: message.
:
: The problem is that ubsan callbacks use spinlocks and might be called
: before lockdep is initialized. Particularly this line in the
: reserve_ebda_region function causes problem:
:
: lowmem = *(unsigned short *)__va(BIOS_LOWMEM_KILOBYTES);
:
: If i put lockdep_init() before reserve_ebda_region call in
: x86_64_start_reservations kernel loads well.
Fix this ordering issue permanently: change lockdep so that it uses
hlists for the hash tables. Unlike a list_head, an hlist_head is in its
initialized state when it is all-zeroes, so lockdep is ready for
operation immediately upon boot - lockdep_init() need not have run.
The patch will also save some memory.
lockdep_init() and lockdep_initialized can be done away with now - a 4.6
patch has been prepared to do this.
Reported-by: Mike Krinkin <krinkin.m.u@gmail.com> Suggested-by: Mike Krinkin <krinkin.m.u@gmail.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vineet Gupta [Fri, 12 Feb 2016 00:13:09 +0000 (16:13 -0800)]
mm,thp: khugepaged: call pte flush at the time of collapse
This showed up on ARC when running LMBench bw_mem tests as Overlapping
TLB Machine Check Exception triggered due to STLB entry (2M pages)
overlapping some NTLB entry (regular 8K page).
bw_mem 2m touches a large chunk of vaddr creating NTLB entries. In the
interim khugepaged kicks in, collapsing the contiguous ptes into a
single pmd. pmdp_collapse_flush()->flush_pmd_tlb_range() is called to
flush out NTLB entries for the ptes. This for ARC (by design) can only
shootdown STLB entries (for pmd). The stray NTLB entries cause the
overlap with the subsequent STLB entry for collapsed page. So make
pmdp_collapse_flush() call pte flush interface not pmd flush.
Note that originally all thp flush call sites in generic code called
flush_tlb_range() leaving it to architecture to implement the flush for
pte and/or pmd. Commit 12ebc1581ad11454 changed this by calling a new
opt-in API flush_pmd_tlb_range() which made the semantics more explicit
but failed to distinguish the pte vs pmd flush in generic code, which is
what this patch fixes.
Note that ARC can fixed w/o touching the generic pmdp_collapse_flush()
by defining a ARC version, but that defeats the purpose of generic
version, plus sementically this is the right thing to do.
Fixes STAR 9000961194: LMBench on AXS103 triggering duplicate TLB
exceptions with super pages
Rasmus Villemoes [Fri, 12 Feb 2016 00:13:06 +0000 (16:13 -0800)]
mm/backing-dev.c: fix error path in wb_init()
We need to use post-decrement to get percpu_counter_destroy() called on
&wb->stat[0]. Moreover, the pre-decremebt would cause infinite
out-of-bounds accesses if the setup code failed at i==0.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Vladimir Davydov <vdavydov@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm, dax: check for pmd_none() after split_huge_pmd()
DAX implements split_huge_pmd() by clearing pmd. This simple approach
reduces memory overhead, as we don't need to deposit page table on huge
page mapping to make split_huge_pmd() never-fail. PTE table can be
allocated and populated later on page fault from backing store.
But one side effect is that have to check if pmd is pmd_none() after
split_huge_pmd(). In most places we do this already to deal with
parallel MADV_DONTNEED.
But I found two call sites which is not affected by MADV_DONTNEED (due
down_write(mmap_sem)), but need to have the check to work with DAX
properly.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The kptr_restrict flag, when set to 1, only prints the kernel address
when the user has CAP_SYSLOG. When it is set to 2, the kernel address
is always printed as zero. When set to 1, this needs to check whether
or not we're in IRQ.
However, when set to 2, this check is unneccessary, and produces
confusing results in dmesg. Thus, only make sure we're not in IRQ when
mode 1 is used, but not mode 2.
[akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Thu, 11 Feb 2016 19:25:55 +0000 (11:25 -0800)]
Merge tag 'gpio-v4.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO fixes from Linus Walleij:
- Probe errorpath fix for the Altera
- irqchip ofnode pointer added to the DaVinci driver
- controller instance number correction for DaVinci
* tag 'gpio-v4.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
gpio: davinci: Fix the number of controllers allocated
gpio: davinci: Add the missing of-node pointer
gpio: gpio-altera: Remove gpiochip on probe failure.
Linus Torvalds [Thu, 11 Feb 2016 19:17:19 +0000 (11:17 -0800)]
Merge tag 'platform-drivers-x86-v4.5-3' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86
Pull x86 platform driver fixes from Darren Hart:
"Just two small fixes for the 4.5-rc cycle:
intel_scu_ipcutil:
- underflow in scu_reg_access()
intel-hid:
- fix incorrect entries in intel_hid_keymap"
* tag 'platform-drivers-x86-v4.5-3' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86:
intel_scu_ipcutil: underflow in scu_reg_access()
intel-hid: fix incorrect entries in intel_hid_keymap
1) Fix BPF handling of branch offset adjustmnets on backjumps, from
Daniel Borkmann.
2) Make sure selinux knows about SOCK_DESTROY netlink messages, from
Lorenzo Colitti.
3) Fix openvswitch tunnel mtu regression, from David Wragg.
4) Fix ICMP handling of TCP sockets in syn_recv state, from Eric
Dumazet.
5) Fix SCTP user hmacid byte ordering bug, from Xin Long.
6) Fix recursive locking in ipv6 addrconf, from Subash Abhinov
Kasiviswanathan.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
bpf: fix branch offset adjustment on backjumps after patching ctx expansion
vxlan, gre, geneve: Set a large MTU on ovs-created tunnel devices
geneve: Relax MTU constraints
vxlan: Relax MTU constraints
flow_dissector: Fix unaligned access in __skb_flow_dissector when used by eth_get_headlen
of: of_mdio: Add marvell, 88e1145 to whitelist of PHY compatibilities.
selinux: nlmsgtab: add SOCK_DESTROY to the netlink mapping tables
sctp: translate network order to host order when users get a hmacid
enic: increment devcmd2 result ring in case of timeout
tg3: Fix for tg3 transmit queue 0 timed out when too many gso_segs
net:Add sysctl_max_skb_frags
tcp: do not drop syn_recv on all icmp reports
ipv6: fix a lockdep splat
unix: correctly track in-flight fds in sending process user_struct
update be2net maintainers' email addresses
dwc_eth_qos: Reset hardware before PHY start
ipv6: addrconf: Fix recursive spin lock call
Eran Ben Elisha [Thu, 11 Feb 2016 08:24:42 +0000 (10:24 +0200)]
IB/core: Fix reading capability mask of the port info class
When checking specific attribute from a bit mask, need to use bitwise
AND and not logical AND, fixed that.
Fixes: 145d9c541032 ('IB/core: Display extended counter set if
available') Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com> Signed-off-by: Matan Barak <matanb@mellanox.com> Reviewed-by: Or Gerlitz <ogerlitz@mellanox.com> Reviewed-by: Christoph Lameter <cl@linux.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
net/mlx4: fix some error handling in mlx4_multi_func_init()
The while loop after err_slaves should use post-decrement; otherwise
we'll fail to do the kfrees for i==0, and will run into out-of-bounds
accesses if the setup above failed already at i==0.
[I'm not sure why one even bothers populating the ->vlan_filter array:
mlx4.h isn't #included by anything outside
drivers/net/ethernet/mellanox/mlx4/, and "git grep -C2 -w vlan_filter
drivers/net/ethernet/mellanox/mlx4/" seems to suggest that the
vlan_filter elements aren't used at all.]
Revert this change as it causes a sysfs path to change and therefore
introduces and ABI regression. More precisely Android's vold is not being
able to access /sys/module/mmcblk/parameters/perdev_minors any more, since
the path becomes changed to: "/sys/module/mmc_block/..."
Fixes: 829b6962f7e3 ("mmc: block: don't use parameter prefix if built as
module") Reported-by: John Stultz <john.stultz@linaro.org> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Javi Merino [Thu, 11 Feb 2016 12:00:51 +0000 (12:00 +0000)]
thermal: cpu_cooling: fix out of bounds access in time_in_idle
In __cpufreq_cooling_register() we allocate the arrays for time_in_idle
and time_in_idle_timestamp to be as big as the number of cpus in this
cpufreq device. However, in get_load() we access this array using the
cpu number as index, which can result in an out of bound access.
Index time_in_idle{,_timestamp} using the index in the cpufreq_device's
allowed_cpus mask, as we do for the load_cpu array in
cpufreq_get_requested_power()
Reported-by: Nicolas Boichat <drinkcat@chromium.org> Cc: Amit Daniel Kachhap <amit.kachhap@gmail.com> Cc: Zhang Rui <rui.zhang@intel.com> Cc: Eduardo Valentin <edubezval@gmail.com> Tested-by: Nicolas Boichat <drinkcat@chromium.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Javi Merino <javi.merino@arm.com> Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
David Sterba [Fri, 13 Nov 2015 12:44:28 +0000 (13:44 +0100)]
btrfs: properly set the termination value of ctx->pos in readdir
The value of ctx->pos in the last readdir call is supposed to be set to
INT_MAX due to 32bit compatibility, unless 'pos' is intentially set to a
larger value, then it's LLONG_MAX.
There's a report from PaX SIZE_OVERFLOW plugin that "ctx->pos++"
overflows (https://forums.grsecurity.net/viewtopic.php?f=1&t=4284), on a
64bit arch, where the value is 0x7fffffffffffffff ie. LLONG_MAX before
the increment.
We can get to that situation like that:
* emit all regular readdir entries
* still in the same call to readdir, bump the last pos to INT_MAX
* next call to readdir will not emit any entries, but will reach the
bump code again, finds pos to be INT_MAX and sets it to LLONG_MAX
Normally this is not a problem, but if we call readdir again, we'll find
'pos' set to LLONG_MAX and the unconditional increment will overflow.
The report from Victor at
(http://thread.gmane.org/gmane.comp.file-systems.btrfs/49500) with debugging
print shows that pattern:
The jump from 7fffffff to 7fffffffffffffff happens when new dir entries
are not yet synced and are processed from the delayed list. Then the code
could go to the bump section again even though it might not emit any new
dir entries from the delayed list.
The fix avoids entering the "bump" section again once we've finished
emitting the entries, both for synced and delayed entries.
References: https://forums.grsecurity.net/viewtopic.php?f=1&t=4284 Reported-by: Victor <services@swwu.com> CC: stable@vger.kernel.org Signed-off-by: David Sterba <dsterba@suse.com> Tested-by: Holger Hoffstätte <holger.hoffstaette@googlemail.com> Signed-off-by: Chris Mason <clm@fb.com>
Linus Walleij [Wed, 10 Feb 2016 08:25:17 +0000 (09:25 +0100)]
ARM: 8519/1: ICST: try other dividends than 1
Since the dawn of time the ICST code has only supported divide
by one or hang in an eternal loop. Luckily we were always dividing
by one because the reference frequency for the systems using
the ICSTs is 24MHz and the [min,max] values for the PLL input
if [10,320] MHz for ICST307 and [6,200] for ICST525, so the loop
will always terminate immediately without assigning any divisor
for the reference frequency.
But for the code to make sense, let's insert the missing i++
Reported-by: David Binderman <dcb314@hotmail.com> Cc: stable@vger.kernel.org Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Adrian Hunter [Tue, 9 Feb 2016 14:12:38 +0000 (16:12 +0200)]
mmc: sdhci-acpi: Fix card detect race for Intel BXT/APL
Intel BXT/APL use a card detect GPIO however the host controller
will not enable bus power unless it's card detect also reflects
the presence of a card. Unfortunately those 2 things race which
can result in commands not starting, after which the controller
does nothing and there is a 10 second wait for the driver's
10-second timer to timeout.
That is fixed by having the driver look also at the present state
register to determine if the card is present. Consequently, provide
a 'get_cd' mmc host operation for BXT/APL that does that.
Adrian Hunter [Tue, 9 Feb 2016 14:12:37 +0000 (16:12 +0200)]
mmc: sdhci-pci: Fix card detect race for Intel BXT/APL
Intel BXT/APL use a card detect GPIO however the host controller
will not enable bus power unless it's card detect also reflects
the presence of a card. Unfortunately those 2 things race which
can result in commands not starting, after which the controller
does nothing and there is a 10 second wait for the driver's
10-second timer to timeout.
That is fixed by having the driver look also at the present state
register to determine if the card is present. Consequently, provide
a 'get_cd' mmc host operation for BXT/APL that does that.
Adrian Hunter [Tue, 9 Feb 2016 14:12:36 +0000 (16:12 +0200)]
mmc: sdhci: Allow override of get_cd() called from sdhci_request()
Drivers may need to provide their own get_cd() mmc host op, but
currently the internals of the current op (sdhci_get_cd()) are
provided by sdhci_do_get_cd() which is also called from
sdhci_request().
To allow override of the get_cd functionality, change sdhci_request()
to call ->get_cd() instead of sdhci_do_get_cd().
Note, in the future the call to ->get_cd() will likely be removed
from sdhci_request() since most drivers don't need actually it.
However this change is being done now to facilitate a subsequent
bug fix.
projects / karo-tx-linux.git / log