Alex Williamson [Wed, 12 May 2010 13:46:31 +0000 (09:46 -0400)]
KVM: remove CAP_SYS_RAWIO requirement from kvm_vm_ioctl_assign_irq
Remove this check in an effort to allow kvm guests to run without
root privileges. This capability check doesn't seem to add any
security since the device needs to have already been added via the
assign device ioctl and the io actually occurs through the pci
sysfs interface.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Dongxiao Xu [Tue, 11 May 2010 10:29:45 +0000 (18:29 +0800)]
KVM: VMX: VMCLEAR/VMPTRLD usage changes
Originally VMCLEAR/VMPTRLD is called on vcpu migration. To
support hosted VMM coexistance, VMCLEAR is executed on vcpu
schedule out, and VMPTRLD is executed on vcpu schedule in.
This could also eliminate the IPI when doing VMCLEAR.
Avi Kivity [Mon, 10 May 2010 09:09:56 +0000 (12:09 +0300)]
KVM: MMU: Fix free memory accounting race in mmu_alloc_roots()
We drop the mmu lock between freeing memory and allocating the roots; this
allows some other vcpu to sneak in and allocate memory.
While the race is benign (resulting only in temporary overallocation, not oom)
it is simple and easy to fix by moving the freeing close to the allocation.
Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Gleb Natapov [Mon, 10 May 2010 08:16:56 +0000 (11:16 +0300)]
KVM: inject #UD if instruction emulation fails and exit to userspace
Do not kill VM when instruction emulation fails. Inject #UD and report
failure to userspace instead. Userspace may choose to reenter guest if
vcpu is in userspace (cpl == 3) in which case guest OS will kill
offending process and continue running.
Gui Jianfeng [Wed, 5 May 2010 01:03:49 +0000 (09:03 +0800)]
KVM: MMU: make kvm_mmu_zap_page() return the number of pages it actually freed
Currently, kvm_mmu_zap_page() returning the number of freed children sp.
This might confuse the caller, because caller don't know the actual freed
number. Let's make kvm_mmu_zap_page() return the number of pages it actually
freed.
Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Joerg Roedel [Wed, 5 May 2010 14:04:44 +0000 (16:04 +0200)]
KVM: SVM: Allow EFER.LMSLE to be set with nested svm
This patch enables setting of efer bit 13 which is allowed
in all SVM capable processors. This is necessary for the
SLES11 version of Xen 4.0 to boot with nested svm.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Avi Kivity [Mon, 3 May 2010 13:54:48 +0000 (16:54 +0300)]
KVM: Get rid of KVM_REQ_KICK
KVM_REQ_KICK poisons vcpu->requests by having a bit set during normal
operation. This causes the fast path check for a clear vcpu->requests
to fail all the time, triggering tons of atomic operations.
Fix by replacing KVM_REQ_KICK with a vcpu->guest_mode atomic.
KVM: x86 emulator: x86_emulate_insn() return -1 only in case of emulation failure
Currently emulator returns -1 when emulation failed or IO is needed.
Caller tries to guess whether emulation failed by looking at other
variables. Make it easier for caller to recognise error condition by
always returning -1 in case of failure. For this new emulator
internal return value X86EMUL_IO_NEEDED is introduced. It is used to
distinguish between error condition (which returns X86EMUL_UNHANDLEABLE)
and condition that requires IO exit to userspace to continue emulation.
Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
KVM: fill in run->mmio details in (read|write)_emulated function
Fill in run->mmio details in (read|write)_emulated function just like
pio does. There is no point in filling only vcpu fields there just to
copy them into vcpu->run a little bit later.
Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
KVM: x86 emulator: fix X86EMUL_RETRY_INSTR and X86EMUL_CMPXCHG_FAILED values
Currently X86EMUL_PROPAGATE_FAULT, X86EMUL_RETRY_INSTR and
X86EMUL_CMPXCHG_FAILED have the same value so caller cannot
distinguish why function such as emulator_cmpxchg_emulated()
(which can return both X86EMUL_PROPAGATE_FAULT and
X86EMUL_CMPXCHG_FAILED) failed.
Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
KVM: x86 emulator: add get_cached_segment_base() callback to x86_emulate_ops
On VMX it is expensive to call get_cached_descriptor() just to get segment
base since multiple vmcs_reads are done instead of only one. Introduce
new call back get_cached_segment_base() for efficiency.
Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
KVM: x86 emulator: handle "far address" source operand
ljmp/lcall instruction operand contains address and segment.
It can be 10 bytes long. Currently we decode it as two different
operands. Fix it by introducing new kind of operand that can hold
entire far address.
Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Introduce read cache which is needed for instruction that require more
then one exit to userspace. After returning from userspace the instruction
will be re-executed with cached read value.
Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Avi Kivity [Mon, 3 May 2010 13:05:44 +0000 (16:05 +0300)]
KVM: VMX: Avoid writing HOST_CR0 every entry
cr0.ts may change between entries, so we copy cr0 to HOST_CR0 before each
entry. That is slow, so instead, set HOST_CR0 to have TS set unconditionally
(which is a safe value), and issue a clts() just before exiting vcpu context
if the task indeed owns the fpu.
KVM: x86: avoid unnecessary bitmap allocation when memslot is clean
Although we always allocate a new dirty bitmap in x86's get_dirty_log(),
it is only used as a zero-source of copy_to_user() and freed right after
that when memslot is clean. This patch uses clear_user() instead of doing
this unnecessary zero-source allocation.
Performance improvement: as we can expect easily, the time needed to
allocate a bitmap is completely reduced. In my test, the improved ioctl
was about 4 to 10 times faster than the original one for clean slots.
Furthermore, reducing memory allocations and copies will produce good
effects to caches too.
Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: Avi Kivity <avi@redhat.com>
Huang Ying [Mon, 31 May 2010 06:28:19 +0000 (14:28 +0800)]
KVM: Avoid killing userspace through guest SRAO MCE on unmapped pages
In common cases, guest SRAO MCE will cause corresponding poisoned page
be un-mapped and SIGBUS be sent to QEMU-KVM, then QEMU-KVM will relay
the MCE to guest OS.
But it is reported that if the poisoned page is accessed in guest
after unmapping and before MCE is relayed to guest OS, userspace will
be killed.
The reason is as follows. Because poisoned page has been un-mapped,
guest access will cause guest exit and kvm_mmu_page_fault will be
called. kvm_mmu_page_fault can not get the poisoned page for fault
address, so kernel and user space MMIO processing is tried in turn. In
user MMIO processing, poisoned page is accessed again, then userspace
is killed by force_sig_info.
To fix the bug, kvm_mmu_page_fault send HWPOISON signal to QEMU-KVM
and do not try kernel and user space MMIO processing for poisoned
page.
[xiao: fix warning introduced by avi]
Reported-by: Max Asbock <masbock@linux.vnet.ibm.com> Signed-off-by: Huang Ying <ying.huang@intel.com> Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6:
[SCSI] ibmvscsi: Fix oops when an interrupt is pending during probe
[SCSI] zfcp: Update status read mempool
[SCSI] zfcp: Do not wait for SBALs on stopped queue
[SCSI] zfcp: Fix check whether unchained ct_els is possible
[SCSI] ipr: fix resource path display and formatting
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lrg/voltage-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lrg/voltage-2.6:
davinci: da850/omap-l138 evm: account for DEFDCDC{2,3} being tied high
regulator: tps6507x: allow driver to use DEFDCDC{2,3}_HIGH register
wm8350-regulator: fix wm8350_register_regulator error handling
ab3100: fix off-by-one value range checking for voltage selector
Andre Osterhues [Tue, 13 Jul 2010 20:59:17 +0000 (15:59 -0500)]
ecryptfs: Bugfix for error related to ecryptfs_hash_buckets
The function ecryptfs_uid_hash wrongly assumes that the
second parameter to hash_long() is the number of hash
buckets instead of the number of hash bits.
This patch fixes that and renames the variable
ecryptfs_hash_buckets to ecryptfs_hash_bits to make it
clearer.
Jason Wessel [Thu, 29 Jul 2010 00:10:30 +0000 (19:10 -0500)]
x86,kgdb: Fix hw breakpoint regression
HW breakpoints events stopped working correctly with kgdb
as a result of commit: 018cbffe6819f6f8db20a0a3acd9bab9bfd667e4
(Merge commit 'v2.6.33' into perf/core).
The regression occurred because the behavior changed for setting
NOTIFY_STOP as the return value to the die notifier if the breakpoint
was known to the HW breakpoint API. Because kgdb is using the HW
breakpoint API to register HW breakpoints slots, it must also now
implement the overflow_handler call back else kgdb does not get to see
the events from the die notifier.
The kgdb_ll_trap function will be changed to be general purpose code
which can allow an easy way to implement the hw_breakpoint API
overflow call back.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Dongdong Deng <dongdong.deng@windriver.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
If we don't need a huge amount of memory in ->readdir() then
we can use kmalloc rather than vmalloc to allocate it. This
should cut down on the greater overheads associated with
vmalloc for smaller directories.
We may be able to eliminate vmalloc entirely at some stage,
but this is easy to do right away.
Also using GFP_NOFS to avoid any issues wrt to deleting inodes
while under a glock, and suggestion from Linus to factor out
the alloc/dealloc.
I've given this a test with a variety of different sized
directories and it seems to work ok.
Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Nick Piggin <npiggin@suse.de> Cc: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sekhar Nori [Mon, 12 Jul 2010 12:26:21 +0000 (17:56 +0530)]
davinci: da850/omap-l138 evm: account for DEFDCDC{2,3} being tied high
Per the da850/omap-l138 Beta EVM SOM schematic, the DEFDCDC2 and DEFDCDC3 lines are tied high. This leads to a 3.3V IO and 1.2V CVDD
voltage.
Pass the right platform data to the TPS6507x driver so it can operate
on the DEFDCDC{2,3}_HIGH register to read and change voltage levels.
Signed-off-by: Sekhar Nori <nsekhar@ti.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
regulator: tps6507x: allow driver to use DEFDCDC{2,3}_HIGH register
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
In TPS6507x, depending on the status of DEFDCDC{2,3} pin either DEFDCDC{2,3}_LOW or DEFDCDC{2,3}_HIGH register needs to be read or
programmed to change the output voltage.
The current driver assumes DEFDCDC{2,3} pins are always tied low
and thus operates only on DEFDCDC{2,3}_LOW register. This need
not always be the case (as is found on OMAP-L138 EVM).
Unfortunately, software cannot read the status of DEFDCDC{2,3} pins.
So, this information is passed through platform data depending on
how the board is wired.
The MPC85xx EDAC driver is missing module device aliases, so the driver
won't load automatically on boot. This patch fixes the issue by adding
proper MODULE_DEVICE_TABLE() macros.
Signed-off-by: Anton Vorontsov <avorontsov@mvista.com> Cc: Doug Thompson <dougthompson@xmission.com> Cc: Peter Tyser <ptyser@xes-inc.com> Cc: Dave Jiang <djiang@mvista.com> Cc: Kumar Gala <galak@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rudolf Marek [Tue, 27 Jul 2010 20:18:02 +0000 (13:18 -0700)]
drivers/rtc/rtc-rx8581.c: fix setdatetime
Fix the logic while writing new date/time to the chip. The driver
incorrectly wrote back register values to different registers and even
with wrong mask. The patch adds clearing of the VLF register, which
should be cleared if all date/time values are set.
Signed-off-by: Rudolf Marek <rudolf.marek@sysgo.com> Acked-by: Wan ZongShun <mcuos.com@gmail.com> Cc: Martyn Welch <martyn.welch@gefanuc.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Move the call to ddebug_remove_module() down into free_module(). In this
way it should be called from all error paths. Currently, we are missing
the remove if the module init routine fails.
Signed-off-by: Jason Baron <jbaron@redhat.com> Reported-by: Thomas Renninger <trenn@suse.de> Tested-by: Thomas Renninger <trenn@suse.de> Cc: <stable@kernel.org> [2.6.32+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This fixes an issue triggered by running concurrent syncs. One of the syncs
would go through while the other would just hang indefinitely. In any case, we
never actually want to wake a single waiter, so the *_all functions should
be used.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net> Signed-off-by: Sage Weil <sage@newdream.net>
srp_task needs to be setup before request_irq. The patch below fixes the oops.
Signed-off-by: Anton Blanchard <anton@samba.org> Acked-by: Brian King <brking@linux.vnet.ibm.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
s2io: fixing DBG_PRINT() macro
ath9k: fix dma direction for map/unmap in ath_rx_tasklet
net: dev_forward_skb should call nf_reset
net sched: fix race in mirred device removal
tun: avoid BUG, dump packet on GSO errors
bonding: set device in RLB ARP packet handler
wimax/i2400m: Add PID & VID for Intel WiMAX 6250
ipv6: Don't add routes to ipv6 disabled interfaces.
net: Fix skb_copy_expand() handling of ->csum_start
net: Fix corruption of skb csum field in pskb_expand_head() of net/core/skbuff.c
macvtap: Limit packet queue length
ixgbe/igb: catch invalid VF settings
bnx2x: Advance a module version
bnx2x: Protect statistics ramrod and sequence number
bnx2x: Protect a SM state change
wireless: use netif_rx_ni in ieee80211_send_layer2_update
Peter Zijlstra [Fri, 9 Jul 2010 08:21:21 +0000 (10:21 +0200)]
perf, powerpc: Use perf_sample_data_init() for the FSL code
We should use perf_sample_data_init() to initialize struct
perf_sample_data. As explained in the description of commit dc1d628a
("perf: Provide generic perf_sample_data initialization"), it is
possible for userspace to get the kernel to dereference data.raw,
so if it is not initialized, that means that unprivileged userspace
can possibly oops the kernel. Using perf_sample_data_init makes sure
it gets initialized to NULL.
This conversion should have been included in commit dc1d628a, but it
got missed.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Kumar Gala <kumar.gala@freescale.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
In the case of platform_device_add() fail, we should call
platform_device_put() instead of platform_device_del()
Signed-off-by: Axel Lin <axel.lin@gmail.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
Axel Lin [Mon, 26 Jul 2010 07:34:14 +0000 (15:34 +0800)]
ab3100: fix off-by-one value range checking for voltage selector
We use voltage selector as an array index for typ_voltages.
Thus the valid range for voltage selector should be 0..voltages_len-1.
Signed-off-by: Axel Lin <axel.lin@gmail.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Linus Walleij <linus.walleij@stericsson.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: Do not try to disable hpet if it hasn't been initialized before
x86, i8259: Only register sysdev if we have a real 8259 PIC
Patch 9e39f7c5b311a306977c5471f9e2ce4c456aa038 changed the
DBG_PRINT() macro and the if clause was wrongly changed. It means
that currently all the DBG_PRINT are being printed, flooding the
kernel log buffer with things like:
s2io: eth6: Next block at: c0000000b9c90000
s2io: eth6: In Neterion Tx routine
Signed-off-by: Breno Leitao <leitao@linux.vnet.ibm.com> Acked-by: Sreenivasa Honnur <Sreenivasa.Honnur@neterion.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/upstream-linus
* 'upstream' of git://git.linux-mips.org/pub/scm/upstream-linus:
MIPS: Set io_map_base for several PCI bridges lacking it
MIPS: Alchemy: Define eth platform devices in the correct order
MIPS: BCM63xx: Prevent second enet registration on BCM6338
MIPS: Quit using undefined behavior of ADDU in 64-bit atomic operations.
MIPS: N32: Define getdents64.
MIPS: MTX-1: Fix PCI on the MeshCube and related boards
MIPS: Make init_vdso a subsys_initcall.
MIPS: "Fix" useless 'init_vdso successfully' message.
MIPS: PowerTV: Move register setup to before reading registers.
SOUND: Au1000: Fix section mismatch
VIDEO: Au1100fb: Fix section mismatch
VIDEO: PMAGB-B: Fix section mismatch
VIDEO: PMAG-BA: Fix section mismatch
NET: declance: Fix section mismatches
VIDEO. gbefb: Fix section mismatches.
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6:
sysfs: allow creating symlinks from untagged to tagged directories
sysfs: sysfs_delete_link handle symlinks from untagged to tagged directories.
sysfs: Don't allow the creation of symlinks we can't remove
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6:
USB: musb: tusb6010: fix compile error with n8x0_defconfig
USB: FTDI: Add support for the RT System VX-7 radio programming cable
USB: add quirk for Broadcom BT dongle
USB: usb-storage: fix initializations of urb fields
USB: xhci: Set Mult field in endpoint context correctly.
USB: sisusbvga: Fix for USB 3.0
USB: adds Artisman USB dongle to list of quirky devices
USB: xhci: Set EP0 dequeue ptr after reset of configured device.
USB: Fix USB3.0 Port Speed Downgrade after port reset
USB: xHCI: Fix another bug in link TRB activation change.
USB: option: Add support for AMOI Skypephone S2
USB: New PIDs for Qualcomm gobi 2000 (qcserial)
USB: ftdi_sio: support for Signalyzer tools based on FTDI chips
USB: s3c2410_udc: be aware of connected gadget driver
USB: Expose vendor-specific ACM channel on Nokia 5230
USB: Add PID for Sierra 250U to drivers/usb/serial/sierra.c
USB: option: add support for 1da5:4518
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel:
drm/i915: add pipe A force quirks to i915 driver
drm/i915: Fix panel fitting regression since 734b4157
drm/i915: fix deadlock in fb teardown
drm/i915: don't free non-existent compressed llb on ILK+
agp/intel: Use the correct mask to detect i830 aperture size.
drm/i915: disable FBC when more than one pipe is active
drm/i915: Use the correct scanout alignment for fbcon.
drm/i915: make sure eDP panel is turned on
drm/i915: add PANEL_UNLOCK_REGS definition
drm/i915: Make G4X-style PLL search more permissive
drm/i915: Clear any existing dither mode prior to enabling spatial dithering
drm/i915: handle shared framebuffers when flipping
drm/i915: Explosion following OOM in do_execbuffer.
gpu/drm/i915: Add a blacklist to omit modeset on LID open
The Pstate transition latency check was added for broken F10h BIOSen
which wrongly contain a value of 0 for transition and bus master
latency. Fam11h and later, however, (will) have similar transition
latency so extend that behavior for them too.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> Signed-off-by: Dave Jones <davej@redhat.com>
Matthew Garrett [Thu, 15 Jul 2010 15:44:00 +0000 (11:44 -0400)]
[CPUFREQ] Fix PCC driver error path
The PCC cpufreq driver unmaps the mailbox address range if any CPUs fail to
initialise, but doesn't do anything to remove the registered CPUs from the
cpufreq core resulting in failures further down the line. We're better off
simply returning a failure - the cpufreq core will unregister us cleanly if
we end up with no successfully registered CPUs. Tidy up the failure path
and also add a sanity check to ensure that the firmware gives us a realistic
frequency - the core deals badly with that being set to 0.
Signed-off-by: Matthew Garrett <mjg@redhat.com> Cc: Naga Chumbalkar <nagananda.chumbalkar@hp.com> Signed-off-by: Dave Jones <davej@redhat.com>
Matthew Garrett [Tue, 20 Jul 2010 17:52:00 +0000 (13:52 -0400)]
[CPUFREQ] pcc driver should check for pcch method before calling _OSC
The pcc specification documents an _OSC method that's incompatible with the
one defined as part of the ACPI spec. This shouldn't be a problem as both
are supposed to be guarded with a UUID. Unfortunately approximately nobody
(including HP, who wrote this spec) properly check the UUID on entry to the
_OSC call. Right now this could result in surprising behaviour if the pcc
driver performs an _OSC call on a machine that doesn't implement the pcc
specification. Check whether the PCCH method exists first in order to reduce
this probability.
Signed-off-by: Matthew Garrett <mjg@redhat.com> Cc: Naga Chumbalkar <nagananda.chumbalkar@hp.com> Signed-off-by: Dave Jones <davej@redhat.com>
395913d0b1db37092ea3d9d69b832183b1dd84c5 ("[CPUFREQ] remove rwsem lock
from CPUFREQ_GOV_STOP call (second call site)") is not needed, because
there is no rwsem lock in cpufreq_ondemand and cpufreq_conservative
anymore. Lock should not be released until the work done.
sysfs: allow creating symlinks from untagged to tagged directories
Supporting symlinks from untagged to tagged directories is reasonable,
and needed to support CONFIG_SYSFS_DEPRECATED. So don't fail a prior
allowing that case to work.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
sysfs: Don't allow the creation of symlinks we can't remove
Recently my tagged sysfs support revealed a flaw in the device core
that a few rare drivers are running into such that we don't always put
network devices in a class subdirectory named net/.
Since we are not creating the class directory the network devices wind
up in a non-tagged directory, but the symlinks to the network devices
from /sys/class/net are in a tagged directory. All of which works
until we go to remove or rename the symlink. When we remove or rename
a symlink we look in the namespace of the target of the symlink.
Since the target of the symlink is in a non-tagged sysfs directory we
don't have a namespace to look in, and we fail to remove the symlink.
Detect this problem up front and simply don't create symlinks we won't
be able to remove later. This prevents symlink leakage and fails in
a much clearer and more understandable way.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Maciej W. Rozycki <macro@linux-mips.org> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
projects / linux-beck.git / log