Rui Teng [Fri, 2 Sep 2016 06:17:26 +0000 (14:17 +0800)]
powerpc: Clean up tm_abort duplication in hash_utils_64.c
The same logic appears twice and should probably be pulled out into a
function.
Suggested-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Rui Teng <rui.teng@linux.vnet.ibm.com>
[mpe: Rename to tm_flush_hash_page() and move comment into the function] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
CLR_TOP32() is defined as blank. Last useful instance of CLR_TOP32()
was removed by commit 40ef8cbc6d360 ("powerpc: Get 64-bit configs to
compile with ARCH=powerpc") in 2005.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
On some CPUs like the 8xx, _PAGE_RW hence _PAGE_WRITE is defined
as 0 and _PAGE_RO has to be set when a page is not writable
_PAGE_RO is defined by default in pte-common.h, however BOOK3S/64
doesn't include that file so _PAGE_RO has to be defined explicitly
in book3s/64/pgtable.h
Fixes: a7b9f671f2d14 ("powerpc32: adds handling of _PAGE_RO") Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Russell Currey [Mon, 12 Sep 2016 04:17:24 +0000 (14:17 +1000)]
powerpc/eeh: Skip finding bus until after failure reporting
In eeh_handle_special_event(), eeh_pe_bus_get() is called before calling
eeh_report_failure() on every device under a PE. If a PE was missing a
bus for some reason, the error would occur before reporting failure, even
though eeh_report_failure() doesn't require a bus.
Fix this by moving the bus retrieval and error check after the
eeh_report_failure() calls.
Signed-off-by: Russell Currey <ruscur@russell.cc> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Russell Currey [Mon, 12 Sep 2016 04:17:23 +0000 (14:17 +1000)]
powerpc/powernv/eeh: Skip finding bus for VF resets
When the PE used in pnv_eeh_reset() is that of a VF,
pnv_eeh_reset_vf_pe() is used. Unlike the other reset functions called
in pnv_eeh_reset(), the VF reset doesn't require a bus, and if a bus was
missing the function would error out before resetting the VF PE.
To avoid this, reorder the VF reset function to occur before finding and
checking the bus.
Signed-off-by: Russell Currey <ruscur@russell.cc> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Russell Currey [Mon, 12 Sep 2016 04:17:22 +0000 (14:17 +1000)]
powerpc/eeh: Null check uses of eeh_pe_bus_get
eeh_pe_bus_get() can return NULL if a PCI bus isn't found for a given PE.
Some callers don't check this, and can cause a null pointer dereference
under certain circumstances.
Fix this by checking NULL everywhere eeh_pe_bus_get() is called.
Fixes: 8a6b1bc70dbb ("powerpc/eeh: EEH core to handle special event") Cc: stable@vger.kernel.org # v3.11+ Signed-off-by: Russell Currey <ruscur@russell.cc> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
When we originally added the ability to split the exception vectors from
the kernel (commit 1f6a93e4c35e ("powerpc: Make it possible to move the
interrupt handlers away from the kernel" 2008-09-15)), the LOAD_HANDLER() macro
used an addi instruction to compute the offset of the common handler
from the kernel base address.
Using addi meant the handler had to be within 32K of the kernel base
address, due to the addi instruction taking a signed immediate value.
That necessitated creating a trampoline for the system call handler,
because system_call_common (in entry64.S) is not linked within 32K of
the kernel base address.
Later in commit 61e2390ede3c ("powerpc: Make load_hander handle upto 64k
offset" 2012-11-15) we changed LOAD_HANDLER to take a 64K offset, by
changing it to use ori.
Although system_call_common is not in head_64.S or exceptions-64s.S, it
is included in head-y, which causes it to be linked early in the kernel
text, so in practice it ends up below 64K. Additionally if it can't be
placed below 64K the linker will fail to build with a "relocation
truncated to fit" error.
So remove the trampoline.
Newer toolchains are able to work out that the ori in LOAD_HANDLER only
takes a 16 bit offset, and so they generate a 16 bit relocation. Older
toolchains (binutils 2.22 at least) are not so smart, so we have to add
the @l annotation to tell the assembler to generate a 16 bit relocation.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
On EEH events the kernel will print a dump of relevant registers.
If EEH is unavailable (i.e. CONFIG_EEH is disabled, a new platform
doesn't have EEH support, etc) this information isn't readily available.
Add a new debugfs handler to trigger a PHB register dump, so that this
information can be made available on demand.
Signed-off-by: Russell Currey <ruscur@russell.cc> Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/64/kexec: Remove BookE special default_machine_kexec_prepare()
The only difference is now the TCE table check which doesn't need
to be ifdef'ed out, it will basically do nothing on BookE (it is
only useful for ancient IBM machines).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/64/kexec: Copy image with MMU off when possible
Currently we turn the MMU off after copying the image, and we make
sure there is no overlap between the hash table and the target pages
in that case.
That doesn't work for Radix however. In that case, the page tables
are scattered and we can't really enforce that the target of the
image isn't overlapping one of them.
So instead, let's turn the MMU off before copying the image in radix
mode. Thankfully, in radix mode, even under a hypervisor, we know we
don't have the same kind of RMA limitations that hash mode has.
While at it, also turn the MMU off early when using hash in non-LPAR
mode, that way we can get rid of the collision check completely.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Just using the hash ops won't work anymore since radix will have
NULL in there. Instead create an mmu_cleanup_all() function which
will do the right thing based on the MMU mode.
For Radix, for now I clear UPRT and the PTCR, effectively switching
back to Radix with no partition table setup.
Currently set it to NULL on BookE thought it might be a good idea
to wipe the TLB there (Scott ?)
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
NO_IRQ has been == 0 on powerpc for just over ten years (since commit 0ebfff1491ef ("[POWERPC] Add new interrupt mapping core and change
platforms to use it")). It's also 0 on most other arches.
Although it's fairly harmless, every now and then it causes confusion
when a driver is built on powerpc and another arch which doesn't define
NO_IRQ. There's at least 6 definitions of NO_IRQ in drivers/, at least
some of which are to work around that problem.
So we'd like to remove it. This is fairly trivial in the arch code, we
just convert:
if (irq == NO_IRQ) to if (!irq)
if (irq != NO_IRQ) to if (irq)
irq = NO_IRQ; to irq = 0;
return NO_IRQ; to return 0;
And a few other odd cases as well.
At least for now we keep the #define NO_IRQ, because there is driver
code that uses NO_IRQ and the fixes to remove those will go via other
trees.
Note we also change some occurrences in PPC sound drivers, drivers/ps3,
and drivers/macintosh.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Michael Neuling [Fri, 16 Sep 2016 04:28:44 +0000 (14:28 +1000)]
MAINTAINERS: Update cxl maintainers
Fred has taken over the cxl maintenance I was doing. This updates the
MAINTAINERS file to reflect this.
It also removes a duplicate entry in the files covered and adds an entry
for the CXL PCI code in arch/powerpc.
Signed-off-by: Michael Neuling <mikey@neuling.org> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Pan Xinhui [Thu, 10 Dec 2015 07:30:02 +0000 (15:30 +0800)]
powerpc/nvram: Fix an incorrect partition merge
When we merge two contiguous partitions whose signatures are marked
NVRAM_SIG_FREE, We need update prev's length and checksum, then write it
to nvram, not cur's. So lets fix this mistake now.
Also use memset instead of strncpy to set the partition's name. It's
more readable if we want to fill up with duplicate chars .
Fixes: fa2b4e54d41f ("powerpc/nvram: Improve partition removal") Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Nicholas Piggin [Thu, 15 Sep 2016 09:04:46 +0000 (19:04 +1000)]
powerpc/64s: Optimise MSR handling in exception handling
mtmsrd with L=1 only affects MSR_EE and MSR_RI bits, and we always
know what state those bits are, so the kernel MSR does not need to be
loaded when modifying them.
mtmsrd is often in the critical execution path, so avoiding dependency
on even L1 load is noticable. On a POWER8 this saves about 3 cycles
from the syscall path, and possibly a few from other exception returns
(not measured).
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Nicholas Piggin [Thu, 15 Sep 2016 09:03:21 +0000 (19:03 +1000)]
powerpc/64: Optimise syscall entry for virtual, relocatable case
The mflr r10 instruction was left over from when the code used LR to
branch to system_call_entry from the exception handler. That was
changed by commit 6a404806dfce ("powerpc: Avoid link stack corruption in
MMU on syscall entry path") to use the count register. The value is
never used now, so mflr can be removed, and r10 can be used for storage
rather than spilling to the SPR scratch register.
The scratch register spill causes a long pipeline stall due to the SPR
read after write. This change brings getppid syscall cost from 406 to
376 cycles on POWER8. getppid for non-relocatable case is 371 cycles.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/mm: Update FORCE_MAX_ZONEORDER range to allow hugetlb w/4K
For hugetlb to work with 4K page size, we need MAX_ORDER to be 13 or
more. When switching from a 64K page size to 4K linux page size using
make oldconfig, we end up with a CONFIG_FORCE_MAX_ZONEORDER value of 9.
This results in a 16M hugepage beiing considered as a gigantic huge page
which in turn results in failure to setup hugepages if gigantic hugepage
support is not enabled.
This also results in kernel crash with 4K radix configuration. We
hit the below BUG_ON on radix:
Nicholas Piggin [Wed, 14 Sep 2016 03:21:47 +0000 (13:21 +1000)]
powerpc/64: Document the syscall ABI
Add some documentation for the 64-bit syscall ABI, which doesn't seem
to be documented elsewhere.
This attempts to document existing practice. The only small discrepancy
is glibc clobbers not quite matching the kernel (e.g., xer, some
vsyscalls trash cr1 whereas glibc only clobbers cr0). These will be
resolved after this document is merged.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Nicholas Piggin [Wed, 14 Sep 2016 03:01:21 +0000 (13:01 +1000)]
powerpc/64: Replay hypervisor maintenance interrupt first
The HMI (Hypervisor Maintenance Interrupt) is defined by the
architecture to be higher priority than other maskable interrupts, so
replay it first, as a best-effort to replay according to hardware
priorities.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Michael Ellerman [Thu, 15 Sep 2016 05:11:59 +0000 (15:11 +1000)]
powerpc: Ensure .mem(init|exit).text are within _stext/_etext
In our linker script we open code the list of text sections, because we
need to include the __ftr_alt sections, which are arch-specific.
This means we can't use TEXT_TEXT as defined in vmlinux.lds.h, and so we
don't have the MEM_KEEP() logic for memory hotplug sections.
If we build the kernel with the gold linker, and with CONFIG_MEMORY_HOTPLUG=y,
we see that functions marked __meminit can end up outside of the
_stext/_etext range, and also outside of _sinittext/_einittext, eg:
Michael Ellerman [Thu, 15 Sep 2016 00:40:20 +0000 (10:40 +1000)]
powerpc: Don't change the section in _GLOBAL()
Currently the _GLOBAL() macro unilaterally sets the assembler section to
".text" at the start of the macro. This is rude as the caller may be
using a different section.
So let the caller decide which section to emit the code into. On big
endian we do need to switch to the ".opd" section to emit the OPD, but
do that with pushsection/popsection, thereby leaving the original
section intact.
I verified that the order of all entries in System.map is unchanged
after this patch. The actual addresses shift around slightly so you
can't just diff the System.map.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Nicholas Piggin [Fri, 16 Sep 2016 10:48:08 +0000 (20:48 +1000)]
powerpc: Use kprobe blacklist for exception handlers
Currently we mark the C implementations of some exception handlers as
__kprobes. This has the effect of putting them in the ".kprobes.text"
section, which separates them from the rest of the text.
Instead we can use the blacklist macros to add the symbols to a
blacklist which kprobes will check. This allows the linker to move
exception handler functions close to callers and avoids trampolines in
larger kernels.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Reword change log a bit] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Simon Guo [Tue, 26 Jul 2016 08:06:01 +0000 (16:06 +0800)]
powerpc: Set used_(vsr|vr|spe) in sigreturn path when MSR bits are active
Normally, when MSR[VSX/VR/SPE] bits == 1, the used_vsr/used_vr/used_spe
bit have already been set. However when loading a signal frame from user
space we need to explicitly set used_vsr/used_vr/used_spe to make them
consistent with the MSR bits from the signal frame.
For example, CRIU application, who utilizes sigreturn to restore
checkpointed process, will lead to the case where MSR[VSX] bit is active
in signal frame, but used_vsr bit is not set in the kernel. (the same
applies to VR/SPE).
This patch fixes this by always setting used_* bit when MSR related bits
are active in signal frame and we are doing sigreturn.
Based on a proposal by Benh.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
[mpe: Massage change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
When set_sl_ops() is called, the adapter data structure is not fully
initialized yet. Therefore the device name is not showing up in the
trace. Fix is simply to get the device name from the pci_dev
structure.
Fixes: 6d382616ac22 ("cxl: Abstract the differences between the PSL and XSL") Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Darren Stevens [Wed, 31 Aug 2016 12:24:45 +0000 (13:24 +0100)]
powerpc/pasemi: Fix device_type of Nemo SB600 node.
The of_node for the SB600 (io-bridge) has its device_type set to
'io-bridge' Set it to 'isa' so that it can be found by
isa_bridge_find_early() instead of using patches in the kernel.
Signed-off-by: Darren Stevens <darren@stevens-zone.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Darren Stevens [Wed, 31 Aug 2016 12:24:40 +0000 (13:24 +0100)]
powerpc/pasemi: Fix Nemo SB600 i8259 interrupts.
The device tree on the Nemo passes all of the i8259 interrupts with
numbers between 212 and 222, and points their interrupt-parent property
to the pasemi-opic, requiring custom patches to the kernel. Fix the
values so that they can be controlled by the generic ppc i8259 code.
Signed-off-by: Darren Stevens <darren@stevens-zone.net>
[mpe: Rework deeply nested if and boundary checks] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Add config option for the Nemo motherboard used in the Amigaone X1000.
This is a custom PASemi board with an AMD SB600 southbridge, and needs
some patches to it device tree. This option will be used to build these
into the kernel
Signed-off-by: Darren Stevens <darren@stevens-zone.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Michael Ellerman [Thu, 11 Aug 2016 06:03:14 +0000 (16:03 +1000)]
powerpc/Makefile: Drop CONFIG_WORD_SIZE for BITS
Commit 2578bfae84a7 ("[POWERPC] Create and use CONFIG_WORD_SIZE") added
CONFIG_WORD_SIZE, and suggests that other arches were going to do
likewise.
But that never happened, powerpc is the only architecture which uses it.
So switch to using a simple make variable, BITS, like x86, sh, sparc and
tile. It is also easier to spell and simpler, avoiding any confusion
about whether it's defined due to ordering of make vs kconfig.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Michael Ellerman [Thu, 11 Aug 2016 06:03:11 +0000 (16:03 +1000)]
powerpc/Makefile: CROSS32AS is unused, remove it
In fact it makes no sense at all to have this defined on little endian
builds. Since we disabled the 32-bit VDSO on little endian, we don't
build any 32-bit code when building a little endian kernel.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Michael Ellerman [Tue, 26 Jul 2016 05:29:30 +0000 (15:29 +1000)]
powerpc/64: Do load of PACAKBASE in LOAD_HANDLER
The LOAD_HANDLER macro requires that you have previously loaded "reg"
with PACAKBASE. Although that gives callers flexibility to get PACAKBASE
in some interesting way, none of the callers actually do that. So fold
the load of PACAKBASE into the macro, making it simpler for callers to
use correctly.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Nick Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Michael Ellerman [Tue, 26 Jul 2016 05:29:29 +0000 (15:29 +1000)]
powerpc/64: Correct comment on LOAD_HANDLER()
The comment for LOAD_HANDLER() was wrong. The part about kdump has not
been true since 1f6a93e4c35e ("powerpc: Make it possible to move the
interrupt handlers away from the kernel").
Describe how it currently works, and combine the two separate comments
into one.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Nick Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Paul Mackerras [Fri, 2 Sep 2016 11:49:21 +0000 (21:49 +1000)]
powerpc/mm: Preserve CFAR value on SLB miss caused by access to bogus address
Currently, if userspace or the kernel accesses a completely bogus address,
for example with any of bits 46-59 set, we first take an SLB miss interrupt,
install a corresponding SLB entry with VSID 0, retry the instruction, then
take a DSI/ISI interrupt because there is no HPT entry mapping the address.
However, by the time of the second interrupt, the Come-From Address Register
(CFAR) has been overwritten by the rfid instruction at the end of the SLB
miss interrupt handler. Since bogus accesses can often be caused by a
function return after the stack has been overwritten, the CFAR value would
be very useful as it could indicate which function it was whose return had
led to the bogus address.
This patch adds code to create a full exception frame in the SLB miss handler
in the case of a bogus address, rather than inserting an SLB entry with a
zero VSID field. Then we call a new slb_miss_bad_addr() function in C code,
which delivers a signal for a user access or creates an oops for a kernel
access. In the latter case the oops message will show the CFAR value at the
time of the access.
In the case of the radix MMU, a segment miss interrupt indicates an access
outside the ranges mapped by the page tables. Previously this was handled
by the code for an unrecoverable SLB miss (one with MSR[RI] = 0), which is
not really correct. With this patch, we now handle these interrupts with
slb_miss_bad_addr(), which is much more consistent.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
In commit 31cdd0c39c75 ("powerpc/xmon: Fix SPR read/write commands and
add command to dump SPRs") I added two uses of the "ld" instruction in
spr_access.S. "ld" is a 64-bit instruction, so shouldn't be used on
32-bit CPUs.
Replace it with PPC_LL which is a macro that gives us either "ld" or
"lwz" depending on whether we're 64 or 32-bit.
Fixes: 31cdd0c39c75 ("powerpc/xmon: Fix SPR read/write commands and add command to dump SPRs") Cc: stable@vger.kernel.org # v4.7+ Reported-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Daniel Axtens [Tue, 6 Sep 2016 05:32:42 +0000 (15:32 +1000)]
powerpc/fadump: Set core e_flags using kernel's ELF ABI version
Firmware Assisted Dump is a facility to dump kernel core with assistance
from firmware. As part of this process the kernel ELF ABI version is
stored in the core file.
Currently fadump.h defines this to 0 if it is not already defined. This
clashes with a define in elf.h which sets it based on the current task -
not based on the kernel's ELF ABI version.
Use the compiler-provided #define _CALL_ELF which tells us the ELF ABI
version of the kernel to set e_flags, this matches what binutils does.
Remove the definition in fadump.h, which becomes unused.
Signed-off-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Daniel Axtens [Tue, 6 Sep 2016 05:32:40 +0000 (15:32 +1000)]
powerpc/sparse: Make a bunch of things static
Squash a bunch of sparse warnings by making things static.
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Daniel Axtens <dja@axtens.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Merge tag 'dm-4.8-fixes-4' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper fixes from Mike Snitzer:
- a stable fix in both DM crypt and DM log-writes for too large bios
(as generated by bcache)
- two other stable fixes for DM log-writes
- a stable fix for a DM crypt bug that could result in freeing pointers
from uninitialized memory in the tfm allocation error path
- a DM bufio cleanup to discontinue using create_singlethread_workqueue()
* tag 'dm-4.8-fixes-4' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm bufio: remove use of deprecated create_singlethread_workqueue()
dm crypt: fix free of bad values after tfm allocation failure
dm crypt: fix error with too large bios
dm log writes: fix check of kthread_run() return value
dm log writes: fix bug with too large bios
dm log writes: move IO accounting earlier to fix error path
Merge branch 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
"I'm still prepping a set of fixes for btrfs fsync, just nailing down a
hard to trigger memory corruption. For now, these are tested and ready."
* 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: fix one bug that process may endlessly wait for ticket in wait_reserve_ticket()
Btrfs: fix endless loop in balancing block groups
Btrfs: kill invalid ASSERT() in process_all_refs()
Merge tag 'char-misc-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver fixes from Greg KH:
"Here are a number of small driver fixes for 4.8-rc5.
The largest thing here is deleting an obsolete driver,
drivers/misc/bh1780gli.c, as the functionality of it was replaced by
an iio driver a while ago.
The other fixes are things that have been reported, or reverts of
broken stuff (the binder change). All of these changes have been in
linux-next for a while with no reported issues"
* tag 'char-misc-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
thunderbolt: Don't declare Falcon Ridge unsupported
thunderbolt: Add support for INTEL_FALCON_RIDGE_2C controller.
thunderbolt: Fix resume quirk for Falcon Ridge 4C.
lkdtm: Mark lkdtm_rodata_do_nothing() notrace
mei: me: disable driver on SPT SPS firmware
Revert "android: binder: fix dangling pointer comparison"
drivers/iio/light/Kconfig: SENSORS_BH1780 cleanup
android: binder: fix dangling pointer comparison
misc: delete bh1780 driver
Merge tag 'driver-core-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core fixes from Greg KH:
"Here are three small fixes for 4.8-rc5.
One for sysfs, one for kernfs, and one documentation fix, all for
reported issues. All of these have been in linux-next for a while"
* tag 'driver-core-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
sysfs: correctly handle read offset on PREALLOC attrs
documentation: drivers/core/of: fix name of of_node symlink
kernfs: don't depend on d_find_any_alias() when generating notifications
Merge tag 'tty-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull serial driver fixes from Greg KH:
"Here are some small serial driver fixes for 4.8-rc5. One fixes an
oft-reported build issue with the fintek driver, another reverts a
patch that was causing problems, one fixes a crash, and some new
device ids were added.
All of these have been in linux-next for a while"
* tag 'tty-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial: 8250: added acces i/o products quad and octal serial cards
serial: 8250_mid: fix divide error bug if baud rate is 0
Revert "tty/serial/8250: use mctrl_gpio helpers"
8250/fintek: rename IRQ_MODE macro
Merge tag 'usb-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB/PHY fixes from Greg KH:
"Here are some USB and PHY driver fixes for 4.8-rc5
Nothing major, lots of little fixes for reported bugs, and a build fix
for a missing .h file that the phy drivers needed. All of these have
been in linux-next for a while with no reported issues"
* tag 'usb-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (24 commits)
usb: musb: Fix locking errors for host only mode
usb: dwc3: gadget: always decrement by 1
usb: dwc3: debug: fix ep name on trace output
usb: gadget: udc: core: don't starve DMA resources
USB: serial: option: add WeTelecom 0x6802 and 0x6803 products
USB: avoid left shift by -1
USB: fix typo in wMaxPacketSize validation
usb: gadget: Add the gserial port checking in gs_start_tx()
usb: dwc3: gadget: don't rely on jiffies while holding spinlock
usb: gadget: fsl_qe_udc: signedness bug in qe_get_frame()
usb: gadget: function: f_rndis: socket buffer may be NULL
usb: gadget: function: f_eem: socket buffer may be NULL
usb: renesas_usbhs: gadget: fix return value check in usbhs_mod_gadget_probe()
usb: dwc2: Add reset control to dwc2
usb: dwc3: core: allow device to runtime_suspend several times
usb: dwc3: pci: runtime_resume child device
USB: serial: option: add WeTelecom WM-D200
usb: chipidea: udc: don't touch DP when controller is in host mode
USB: serial: mos7840: fix non-atomic allocation in write path
USB: serial: mos7720: fix non-atomic allocation in write path
...
devpts: return NULL pts 'priv' entry for non-devpts nodes
In commit 8ead9dd54716 ("devpts: more pty driver interface cleanups") I
made devpts_get_priv() just return the dentry->fs_data directly. And
because I thought it wouldn't happen, I added a warning if you ever saw
a pts node that wasn't on devpts.
And no, that warning never triggered under any actual real use, but you
can trigger it by creating nonsensical pts nodes by hand.
So just revert the warning, and make devpts_get_priv() return NULL for
that case like it used to.
Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: stable@vger.kernel.org # 4.6+ Cc: Eric W Biederman" <ebiederm@xmission.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
"A collection of fixes for the nvme over fabrics code"
* 'for-linus' of git://git.kernel.dk/linux-block:
nvme-rdma: Get rid of redundant defines
nvme-rdma: Get rid of duplicate variable
nvme: fabrics drivers don't need the nvme-pci driver
nvme-fabrics: get a reference when reusing a nvme_host structure
nvme-fabrics: change NQN UUID to big-endian format
nvme-loop: set sqsize to 0-based value, per spec
nvme-rdma: fix sqsize/hsqsize per spec
fabrics: define admin sqsize min default, per spec
nvmet-rdma: +1 to *queue_size from hsqsize/hrqsize
nvmet-rdma: Fix use after free
nvme-rdma: initialize ret to zero to avoid returning garbage
Jarkko Sakkinen [Thu, 1 Sep 2016 23:36:58 +0000 (02:36 +0300)]
tpm: invalid self test error message
The driver emits invalid self test error message even though the init
succeeds.
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Fixes: cae8b441fc20 ("tpm: Factor out common startup code") Reviewed-by: James Morris <james.l.morris@oracle.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
Merge tag 'acpi-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI fixes ffrom Rafael Wysocki:
"Two stable-candidate fixes for the ACPI early device probing code
added during the 4.4 cycle, one fixing a typo in a stub macro used
when CONFIG_ACPI is unset and one that prevents sleeping functions
from being called under a spinlock (Lorenzo Pieralisi)"
* tag 'acpi-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI / drivers: replace acpi_probe_lock spinlock with mutex
ACPI / drivers: fix typo in ACPI_DECLARE_PROBE_ENTRY macro
Merge tag 'pm-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
"This includes a stable-candidate cpufreq-dt driver problem fix and
annotations of tracepoints in the runtime PM framework.
Specifics:
- Fix the definition of the cpufreq-dt driver's machines table
introduced during the 4.7 cycle that should be NULL-terminated, but
the termination entry is missing from it (Wei Yongjun).
- Annotate tracepoints in the runtime PM framework's core so as to
allow the functions containing them to be called from the idle code
path without causing RCU to complain about illegal usage (Paul
McKenney)"
* tag 'pm-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / runtime: Add _rcuidle suffix to allow rpm_idle() use from idle
PM / runtime: Add _rcuidle suffix to allow rpm_resume() to be called from idle
cpufreq: dt: Add terminate entry for of_device_id tables
Merge branches 'pm-cpufreq-fixes' and 'pm-core-fixes'
* pm-cpufreq-fixes:
cpufreq: dt: Add terminate entry for of_device_id tables
* pm-core-fixes:
PM / runtime: Add _rcuidle suffix to allow rpm_idle() use from idle
PM / runtime: Add _rcuidle suffix to allow rpm_resume() to be called from idle
ACPI / drivers: replace acpi_probe_lock spinlock with mutex
Commit e647b532275b ("ACPI: Add early device probing infrastructure")
introduced code that allows inserting driver specific
struct acpi_probe_entry probe entries into ACPI linker sections
(one per-subsystem, eg irqchip, clocksource) that are then walked
to retrieve the data and function hooks required to probe the
respective kernel components.
Probing for all entries in a section is triggered through
the __acpi_probe_device_table() function, that in turn, according
to the table ID a given probe entry reports parses the table
with the function retrieved from the respective section structures
(ie struct acpi_probe_entry). Owing to the current ACPI table
parsing implementation, the __acpi_probe_device_table() function
has to share global variables with the acpi_match_madt() function, so
in order to guarantee mutual exclusion locking is required
between the two functions.
Current kernel code implements the locking through the acpi_probe_lock
spinlock; this has the side effect of requiring all code called
within the lock (ie struct acpi_probe_entry.probe_{table/subtbl} hooks)
not to sleep.
However, kernel subsystems that make use of the early probing
infrastructure are relying on kernel APIs that may sleep (eg
irq_domain_alloc_fwnode(), among others) in the function calls
pointed at by struct acpi_probe_entry.{probe_table/subtbl} entries
(eg gic_v2_acpi_init()), which is a bug.
Since __acpi_probe_device_table() is called from context
that is allowed to sleep the acpi_probe_lock spinlock can be replaced
with a mutex; this fixes the issue whilst still guaranteeing
mutual exclusion.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Fixes: e647b532275b (ACPI: Add early device probing infrastructure) Cc: 4.4+ <stable@vger.kernel.org> # 4.4+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI / drivers: fix typo in ACPI_DECLARE_PROBE_ENTRY macro
When the ACPI_DECLARE_PROBE_ENTRY macro was added in
commit e647b532275b ("ACPI: Add early device probing infrastructure"),
a stub macro adding an unused entry was added for the !CONFIG_ACPI
Kconfig option case to make sure kernel code making use of the
macro did not require to be guarded within CONFIG_ACPI in order to
be compiled.
The stub macro was never used since all kernel code that defines
ACPI_DECLARE_PROBE_ENTRY entries is currently guarded within
CONFIG_ACPI; it contains a typo that should be nonetheless fixed.
Fix the typo in the stub (ie !CONFIG_ACPI) ACPI_DECLARE_PROBE_ENTRY()
macro so that it can actually be used if needed.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Fixes: e647b532275b (ACPI: Add early device probing infrastructure) Cc: 4.4+ <stable@vger.kernel.org> # 4.4+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
x86/AMD: Apply erratum 665 on machines without a BIOS fix
AMD F12h machines have an erratum which can cause DIV/IDIV to behave
unpredictably. The workaround is to set MSRC001_1029[31] but sometimes
there is no BIOS update containing that workaround so let's do it
ourselves unconditionally. It is simple enough.
Steven Rostedt [Wed, 25 May 2016 17:47:26 +0000 (13:47 -0400)]
x86/paravirt: Do not trace _paravirt_ident_*() functions
Łukasz Daniluk reported that on a RHEL kernel that his machine would lock up
after enabling function tracer. I asked him to bisect the functions within
available_filter_functions, which he did and it came down to three:
_paravirt_nop(), _paravirt_ident_32() and _paravirt_ident_64()
It was found that this is only an issue when noreplace-paravirt is added
to the kernel command line.
This means that those functions are most likely called within critical
sections of the funtion tracer, and must not be traced.
In newer kenels _paravirt_nop() is defined within gcc asm(), and is no
longer an issue. But both _paravirt_ident_{32,64}() causes the
following splat when they are traced:
Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull overlayfs fixes from Miklos Szeredi:
"Most of this is regression fixes for posix acl behavior introduced in
4.8-rc1 (these were caught by the pjd-fstest suite). The are also
miscellaneous fixes marked as stable material and cleanups.
Other than overlayfs code, it touches <linux/fs.h> to add a constant
with which to disable posix acl caching. No changes needed to the
actual caching code, it automatically does the right thing, although
later we may want to optimize this case.
I'm now testing overlayfs with the following test suites to catch
regressions:
- unionmount-testsuite
- xfstests
- pjd-fstest"
* 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
ovl: update doc
ovl: listxattr: use strnlen()
ovl: Switch to generic_getxattr
ovl: copyattr after setting POSIX ACL
ovl: Switch to generic_removexattr
ovl: Get rid of ovl_xattr_noacl_handlers array
ovl: Fix OVL_XATTR_PREFIX
ovl: fix spelling mistake: "directries" -> "directories"
ovl: don't cache acl on overlay layer
ovl: use cached acl on underlying layer
ovl: proper cleanup of workdir
ovl: remove posix_acl_default from workdir
ovl: handle umask and posix_acl_default correctly on creation
ovl: don't copy up opaqueness
James Morse [Fri, 26 Aug 2016 15:03:42 +0000 (16:03 +0100)]
arm64: kernel: Fix unmasked debug exceptions when restoring mdscr_el1
Changes to make the resume from cpu_suspend() code behave more like
secondary boot caused debug exceptions to be unmasked early by
__cpu_setup(). We then go on to restore mdscr_el1 in cpu_do_resume(),
potentially taking break or watch points based on uninitialised registers.
Mask debug exceptions in cpu_do_resume(), which is specific to resume
from cpu_suspend(). Debug exceptions will be restored to their original
state by local_dbg_restore() in cpu_suspend(), which runs after
hw_breakpoint_restore() has re-initialised the other registers.
Reported-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Fixes: cabe1c81ea5b ("arm64: Change cpu_resume() to enable mmu early then access sleep_sp by va") Cc: <stable@vger.kernel.org> # 4.7+ Signed-off-by: James Morse <james.morse@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Stefan Wahren [Sat, 27 Aug 2016 16:19:50 +0000 (16:19 +0000)]
drivers/perf: arm_pmu: Fix NULL pointer dereference during probe
Patch 7f1d642fbb5c ("drivers/perf: arm-pmu: Fix handling of SPI lacking
interrupt-affinity property") unintended also fixes perf_event support
for bcm2835 which doesn't have PMU interrupts. Unfortunately this change
introduce a NULL pointer dereference on bcm2835, because irq_is_percpu
always expected to be called with a valid IRQ. So fix this regression
by validating the IRQ before.
Tested-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> Fixes: 7f1d642fbb5c ("drivers/perf: arm-pmu: Fix handling of SPI lacking "interrupt-affinity" property") Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Merge tag 'dmaengine-fix-4.8-rc5' of git://git.infradead.org/users/vkoul/slave-dma
Pull dmaengine fixes from Vinod Koul:
"The fixes this time are all in drivers:
- possible NULL dereference in img-mdc
- correct device identity for free_irq in at_xdmac
- missing of_node_put() in fsl probe
- fix debug log and hotchain corner case for pxa-dma
- fix checking hardware bits in isr in usb dmac"
* tag 'dmaengine-fix-4.8-rc5' of git://git.infradead.org/users/vkoul/slave-dma:
dmaengine: img-mdc: fix a possible NULL dereference
dmaengine: at_xdmac: fix to pass correct device identity to free_irq()
dmaengine: fsl_raid: add missing of_node_put() in fsl_re_probe()
dmaengine: pxa_dma: fix debug message
dmaengine: pxa_dma: fix hotchain corner case
dmaengine: usb-dmac: check CHCR.DE bit in usb_dmac_isr_channel()
Merge tag 'drm-fixes-for-4.8-rc5' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
"Contains fixes for imx, amdgpu, vc4, msm and one nouveau ACPI fix"
* tag 'drm-fixes-for-4.8-rc5' of git://people.freedesktop.org/~airlied/linux:
drm/amdgpu: record error code when ring test failed
drm/amd/amdgpu: compute ring test fail during S4 on CI
drm/amd/amdgpu: sdma resume fail during S4 on CI
drm/nouveau/acpi: use DSM if bridge does not support D3cold
drm/imx: fix crtc vblank state regression
drm/imx: Add active plane reconfiguration support
drm/msm: protect against faults from copy_from_user() in submit ioctl
drm/msm: fix use of copy_from_user() while holding spinlock
drm/vc4: Fix oops when userspace hands in a bad BO.
drm/vc4: Fix overflow mem unreferencing when the binner runs dry.
drm/vc4: Free hang state before destroying BO cache.
drm/vc4: Fix handling of a pm_runtime_get_sync() success case.
drm/vc4: Use drm_malloc_ab to fix large rendering jobs.
drm/vc4: Use drm_free_large() on handles to match its allocation.
Wanpeng Li [Fri, 2 Sep 2016 06:38:23 +0000 (14:38 +0800)]
tick/nohz: Fix softlockup on scheduler stalls in kvm guest
tick_nohz_start_idle() is prevented to be called if the idle tick can't
be stopped since commit 1f3b0f8243cb934 ("tick/nohz: Optimize nohz idle
enter"). As a result, after suspend/resume the host machine, full dynticks
kvm guest will softlockup:
The idle and iowait states are weird 0 for cpu0(housekeeping).
The bug is present in both guest and host kernels, and they both have
cpu0's idle and iowait states issue, however, host kernel's suspend/resume
path etc will touch watchdog to avoid the softlockup.
- The watchdog will not be touched in tick_nohz_stop_idle path (need be
touched since the scheduler stall is expected) if idle_active flags are
not detected.
- The idle and iowait states will not be accounted when exit idle loop
(resched or interrupt) if idle start time and idle_active flags are
not set.
This patch fixes it by reverting commit 1f3b0f8243cb934 since can't stop
idle tick doesn't mean can't be idle.
Fixes: 1f3b0f8243cb934 ("tick/nohz: Optimize nohz idle enter") Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Cc: Sanjeev Yadav<sanjeev.yadav@spreadtrum.com> Cc: Gaurav Jindal<gaurav.jindal@spreadtrum.com> Cc: stable@vger.kernel.org Cc: kvm@vger.kernel.org Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Link: http://lkml.kernel.org/r/1472798303-4154-1-git-send-email-wanpeng.li@hotmail.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Dave Airlie [Fri, 2 Sep 2016 05:55:15 +0000 (15:55 +1000)]
Merge tag 'drm-vc4-fixes-2016-08-29' of https://github.com/anholt/linux into drm-fixes
This pull request brings in fixes for VC4 3D in 4.8, most of which are
covered by testcases.
* tag 'drm-vc4-fixes-2016-08-29' of https://github.com/anholt/linux:
drm/vc4: Fix oops when userspace hands in a bad BO.
drm/vc4: Fix overflow mem unreferencing when the binner runs dry.
drm/vc4: Free hang state before destroying BO cache.
drm/vc4: Fix handling of a pm_runtime_get_sync() success case.
drm/vc4: Use drm_malloc_ab to fix large rendering jobs.
drm/vc4: Use drm_free_large() on handles to match its allocation.
Dave Airlie [Fri, 2 Sep 2016 05:48:38 +0000 (15:48 +1000)]
Merge tag 'imx-drm-fixes-2016-08-30' of git://git.pengutronix.de/git/pza/linux into drm-fixes
imx-drm atomic modeset regression fixes
- add active plane reconfiguration support
- add back crtc vblank state reporting
* tag 'imx-drm-fixes-2016-08-30' of git://git.pengutronix.de/git/pza/linux:
drm/imx: fix crtc vblank state regression
drm/imx: Add active plane reconfiguration support
Merge tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux
Pull clk fixes from Stephen Boyd:
"A collection of small fixes for various SoC vendor clk drivers"
* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
clk: rockchip: mark aclk_emmc_noc as a critical clock on rk3399
clk: tegra: remove TEGRA_PLL_USE_LOCK for PLLD/PLLD2
clk: rockchip: fix incorrect GATE bits for {c, g}pll_aclk_perihp_src on rk3399
clk: rockchip: fix incorrect aclk_emmc source gate bits on rk3399
clk: renesas: r8a7795: Fix SD clocks
clk: rockchip: fix rk3399 aclk_vio gate bit
clk: sunxi-ng: Fix inverted test condition in ccu_helper_wait_for_lock
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
rapidio/tsi721: fix incorrect detection of address translation condition
rapidio/documentation/mport_cdev: add missing parameter description
kernel/fork: fix CLONE_CHILD_CLEARTID regression in nscd
MAINTAINERS: Vladimir has moved
mm, mempolicy: task->mempolicy must be NULL before dropping final reference
printk/nmi: avoid direct printk()-s from __printk_nmi_flush()
treewide: remove references to the now unnecessary DEFINE_PCI_DEVICE_TABLE
drivers/scsi/wd719x.c: remove last declaration using DEFINE_PCI_DEVICE_TABLE
mm, vmscan: only allocate and reclaim from zones with pages managed by the buddy allocator
lib/test_hash.c: fix warning in preprocessor symbol evaluation
lib/test_hash.c: fix warning in two-dimensional array init
kconfig: tinyconfig: provide whole choice blocks to avoid warnings
kexec: fix double-free when failing to relocate the purgatory
mm, oom: prevent premature OOM killer invocation for high order request
Michal Hocko [Thu, 1 Sep 2016 23:15:13 +0000 (16:15 -0700)]
kernel/fork: fix CLONE_CHILD_CLEARTID regression in nscd
Commit fec1d0115240 ("[PATCH] Disable CLONE_CHILD_CLEARTID for abnormal
exit") has caused a subtle regression in nscd which uses
CLONE_CHILD_CLEARTID to clear the nscd_certainly_running flag in the
shared databases, so that the clients are notified when nscd is
restarted. Now, when nscd uses a non-persistent database, clients that
have it mapped keep thinking the database is being updated by nscd, when
in fact nscd has created a new (anonymous) one (for non-persistent
databases it uses an unlinked file as backend).
The original proposal for the CLONE_CHILD_CLEARTID change claimed
(https://lkml.org/lkml/2006/10/25/233):
: The NPTL library uses the CLONE_CHILD_CLEARTID flag on clone() syscalls
: on behalf of pthread_create() library calls. This feature is used to
: request that the kernel clear the thread-id in user space (at an address
: provided in the syscall) when the thread disassociates itself from the
: address space, which is done in mm_release().
:
: Unfortunately, when a multi-threaded process incurs a core dump (such as
: from a SIGSEGV), the core-dumping thread sends SIGKILL signals to all of
: the other threads, which then proceed to clear their user-space tids
: before synchronizing in exit_mm() with the start of core dumping. This
: misrepresents the state of process's address space at the time of the
: SIGSEGV and makes it more difficult for someone to debug NPTL and glibc
: problems (misleading him/her to conclude that the threads had gone away
: before the fault).
:
: The fix below is to simply avoid the CLONE_CHILD_CLEARTID action if a
: core dump has been initiated.
The resulting patch from Roland (https://lkml.org/lkml/2006/10/26/269)
seems to have a larger scope than the original patch asked for. It
seems that limitting the scope of the check to core dumping should work
for SIGSEGV issue describe above.
[Changelog partly based on Andreas' description] Fixes: fec1d0115240 ("[PATCH] Disable CLONE_CHILD_CLEARTID for abnormal exit") Link: http://lkml.kernel.org/r/1471968749-26173-1-git-send-email-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Tested-by: William Preston <wpreston@suse.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Cc: Roland McGrath <roland@hack.frob.com> Cc: Andreas Schwab <schwab@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Rientjes [Thu, 1 Sep 2016 23:15:07 +0000 (16:15 -0700)]
mm, mempolicy: task->mempolicy must be NULL before dropping final reference
KASAN allocates memory from the page allocator as part of
kmem_cache_free(), and that can reference current->mempolicy through any
number of allocation functions. It needs to be NULL'd out before the
final reference is dropped to prevent a use-after-free bug:
BUG: KASAN: use-after-free in alloc_pages_current+0x363/0x370 at addr ffff88010b48102c
CPU: 0 PID: 15425 Comm: trinity-c2 Not tainted 4.8.0-rc2+ #140
...
Call Trace:
dump_stack
kasan_object_err
kasan_report_error
__asan_report_load2_noabort
alloc_pages_current <-- use after free
depot_save_stack
save_stack
kasan_slab_free
kmem_cache_free
__mpol_put <-- free
do_exit
This patch sets current->mempolicy to NULL before dropping the final
reference.
printk/nmi: avoid direct printk()-s from __printk_nmi_flush()
__printk_nmi_flush() can be called from nmi_panic(), therefore it has to
test whether it's executed in NMI context and thus must route the
messages through deferred printk() or via direct printk().
This is to avoid potential deadlocks, as described in commit cf9b1106c81c ("printk/nmi: flush NMI messages on the system panic").
However there remain two places where __printk_nmi_flush() does
unconditional direct printk() calls:
Factor out print_nmi_seq_line() parts into a new printk_nmi_flush_line()
function, which takes care of in_nmi(), and use it in
__printk_nmi_flush() for printing and error-reporting.
Link: http://lkml.kernel.org/r/20160830161354.581-1-sergey.senozhatsky@gmail.com Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
projects / linux-beck.git / log