Age | Commit message (Collapse) | Author |
|
Currently trace_clock timestamps are applied to both regular and max
buffers only for global trace. For instance trace, trace_clock
timestamps are applied only to regular buffer. But, regular and max
buffers can be swapped, for example, following a snapshot. So, for
instance trace, bad timestamps can be seen following a snapshot.
Let's apply trace_clock timestamps to instance max buffer as well.
Link: http://lkml.kernel.org/r/ebdb168d0be042dcdf51f81e696b17fabe3609c1.1504642143.git.tom.zanussi@linux.intel.com
Cc: stable@vger.kernel.org
Fixes: 277ba0446 ("tracing: Add interface to allow multiple trace buffers")
Signed-off-by: Baohong Liu <baohong.liu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
|
When disabling one trace event, the RECORDED_TGID flag in the event
file is not correctly cleared. It's clearing RECORDED_CMD flag when
it should clear RECORDED_TGID flag.
Link: http://lkml.kernel.org/r/1504589806-8425-1-git-send-email-chuhu@redhat.com
Cc: Joel Fernandes <joelaf@google.com>
Cc: stable@vger.kernel.org
Fixes: d914ba37d7 ("tracing: Add support for recording tgid of tasks")
Signed-off-by: Chunyu Hu <chuhu@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
|
trace_printk() uses 4 buffers, one for each context (normal, softirq, irq
and NMI), such that it does not need to worry about one context preempting
the other. There's a nesting counter that gets incremented to figure out
which buffer to use. If the context gets preempted by another context which
calls trace_printk() it will increment the counter and use the next buffer,
and restore the counter when it is finished.
The problem is that gcc may optimize the modification of the buffer nesting
counter and it may not be incremented in memory before the buffer is used.
If this happens, and the context gets interrupted by another context, it
could pick the same buffer and corrupt the one that is being used.
Compiler barriers need to be added after the nesting variable is incremented
and before it is decremented to prevent usage of the context buffers by more
than one context at the same time.
Cc: Andy Lutomirski <luto@kernel.org>
Cc: stable@vger.kernel.org
Fixes: e2ace00117 ("tracing: Choose static tp_printk buffer by explicit nesting count")
Hat-tip-to: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
|
If function tracing is disabled by the user via the function-trace option or
the proc sysctl file, and a ftrace_ops that was allocated on the heap is
unregistered, then the shutdown code exits out without doing the proper
clean up. This was found via kmemleak and running the ftrace selftests, as
one of the tests unregisters with function tracing disabled.
# cat kmemleak
unreferenced object 0xffffffffa0020000 (size 4096):
comm "swapper/0", pid 1, jiffies 4294668889 (age 569.209s)
hex dump (first 32 bytes):
55 ff 74 24 10 55 48 89 e5 ff 74 24 18 55 48 89 U.t$.UH...t$.UH.
e5 48 81 ec a8 00 00 00 48 89 44 24 50 48 89 4c .H......H.D$PH.L
backtrace:
[<ffffffff81d64665>] kmemleak_vmalloc+0x85/0xf0
[<ffffffff81355631>] __vmalloc_node_range+0x281/0x3e0
[<ffffffff8109697f>] module_alloc+0x4f/0x90
[<ffffffff81091170>] arch_ftrace_update_trampoline+0x160/0x420
[<ffffffff81249947>] ftrace_startup+0xe7/0x300
[<ffffffff81249bd2>] register_ftrace_function+0x72/0x90
[<ffffffff81263786>] trace_selftest_ops+0x204/0x397
[<ffffffff82bb8971>] trace_selftest_startup_function+0x394/0x624
[<ffffffff81263a75>] run_tracer_selftest+0x15c/0x1d7
[<ffffffff82bb83f1>] init_trace_selftests+0x75/0x192
[<ffffffff81002230>] do_one_initcall+0x90/0x1e2
[<ffffffff82b7d620>] kernel_init_freeable+0x350/0x3fe
[<ffffffff81d61ec3>] kernel_init+0x13/0x122
[<ffffffff81d72c6a>] ret_from_fork+0x2a/0x40
[<ffffffffffffffff>] 0xffffffffffffffff
Cc: stable@vger.kernel.org
Fixes: 12cce594fa ("ftrace/x86: Allow !CONFIG_PREEMPT dynamic ops to use allocated trampolines")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
|
In the second iteration of trace_selftest_ops(), the error goto label is
wrong in the case where trace_selftest_test_global_cnt is off. In the
case of error, it leaks the dynamic ops that was allocated.
Cc: stable@vger.kernel.org
Fixes: 95950c2e ("ftrace: Add self-tests for multiple function trace users")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
|
When a ftrace filter has a module function, and that module is removed, the
filter still has its address as being enabled. This can cause interesting
side effects. Nothing dangerous, but unwanted functions can be traced
because of it.
# cd /sys/kernel/tracing
# echo ':mod:snd_seq' > set_ftrace_filter
# cat set_ftrace_filter
snd_use_lock_sync_helper [snd_seq]
check_event_type_and_length [snd_seq]
snd_seq_ioctl_pversion [snd_seq]
snd_seq_ioctl_client_id [snd_seq]
snd_seq_ioctl_get_queue_tempo [snd_seq]
update_timestamp_of_queue [snd_seq]
snd_seq_ioctl_get_queue_status [snd_seq]
snd_seq_set_queue_tempo [snd_seq]
snd_seq_ioctl_set_queue_tempo [snd_seq]
snd_seq_ioctl_get_queue_timer [snd_seq]
seq_free_client1 [snd_seq]
[..]
# rmmod snd_seq
# cat set_ftrace_filter
# modprobe kvm
# cat set_ftrace_filter
kvm_set_cr4 [kvm]
kvm_emulate_hypercall [kvm]
kvm_set_dr [kvm]
This is because removing the snd_seq module after it was being filtered,
left the address of the snd_seq functions in the hash. When the kvm module
was loaded, some of its functions were loaded at the same address as the
snd_seq module. This would enable them to be filtered and traced.
Now we don't want to clear the hash completely. That would cause removing a
module where only its functions are filtered, to cause the tracing to enable
all functions, as an empty filter means to trace all functions. Instead,
just set the hash ip address to zero. Then it will never match any function.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
|
Currently, when a module event is enabled, when that module is removed, it
clears all ring buffers. This is to prevent another module from being loaded
and having one of its trace event IDs from reusing a trace event ID of the
removed module. This could cause undesirable effects as the trace event of
the new module would be using its own processing algorithms to process raw
data of another event. To prevent this, when a module is loaded, if any of
its events have been used (signified by the WAS_ENABLED event call flag,
which is never cleared), all ring buffers are cleared, just in case any one
of them contains event data of the removed event.
The problem is, there's no reason to clear all ring buffers if only one (or
less than all of them) uses one of the events. Instead, only clear the ring
buffers that recorded the events of a module that is being removed.
To do this, instead of keeping the WAS_ENABLED flag with the trace event
call, move it to the per instance (per ring buffer) event file descriptor.
The event file descriptor maps each event to a separate ring buffer
instance. Then when the module is removed, only the ring buffers that
activated one of the module's events get cleared. The rest are not touched.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
|
stack_tracer_disable()/stack_tracer_enable() had been using the wrong
name for the config symbol to enable their preempt-debugging checks --
fix with a word swap.
Link: http://lkml.kernel.org/r/20170831154036.4xldyakmmhuts5x7@hatter.bewilderbeest.net
Cc: stable@vger.kernel.org
Fixes: 8aaf1ee70e ("tracing: Rename trace_active to disable_stack_tracer and inline its modification")
Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
|
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU fix from Joerg Roedel:
"Another fix, this time in common IOMMU sysfs code.
In the conversion from the old iommu sysfs-code to the
iommu_device_register interface, I missed to update the release path
for the struct device associated with an IOMMU. It freed the 'struct
device', which was a pointer before, but is now embedded in another
struct.
Freeing from the middle of allocated memory had all kinds of nasty
side effects when an IOMMU was unplugged. Unfortunatly nobody
unplugged and IOMMU until now, so this was not discovered earlier. The
fix is to make the 'struct device' a pointer again"
* tag 'iommu-fixes-v4.13-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
iommu: Fix wrong freeing of iommu_device->dev
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc fix from Greg KH:
"Here is a single misc driver fix for 4.13-rc7. It resolves a reported
problem in the Android binder driver due to previous patches in
4.13-rc.
It's been in linux-next with no reported issues"
* tag 'char-misc-4.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
ANDROID: binder: fix proc->tsk check.
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging/iio fixes from Greg KH:
"Here are few small staging driver fixes, and some more IIO driver
fixes for 4.13-rc7. Nothing major, just resolutions for some reported
problems.
All of these have been in linux-next with no reported problems"
* tag 'staging-4.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
iio: magnetometer: st_magn: remove ihl property for LSM303AGR
iio: magnetometer: st_magn: fix status register address for LSM303AGR
iio: hid-sensor-trigger: Fix the race with user space powering up sensors
iio: trigger: stm32-timer: fix get trigger mode
iio: imu: adis16480: Fix acceleration scale factor for adis16480
PATCH] iio: Fix some documentation warnings
staging: rtl8188eu: add RNX-N150NUB support
Revert "staging: fsl-mc: be consistent when checking strcmp() return"
iio: adc: stm32: fix common clock rate
iio: adc: ina219: Avoid underflow for sleeping time
iio: trigger: stm32-timer: add enable attribute
iio: trigger: stm32-timer: fix get/set down count direction
iio: trigger: stm32-timer: fix write_raw return value
iio: trigger: stm32-timer: fix quadrature mode get routine
iio: bmp280: properly initialize device for humidity reading
|
|
Pull NTB fixes from Jon Mason:
"NTB bug fixes to address an incorrect ntb_mw_count reference in the
NTB transport, improperly bringing down the link if SPADs are
corrupted, and an out-of-order issue regarding link negotiation and
data passing"
* tag 'ntb-4.13-bugfixes' of git://github.com/jonmason/ntb:
ntb: ntb_test: ensure the link is up before trying to configure the mws
ntb: transport shouldn't disable link due to bogus values in SPADs
ntb: use correct mw_count function in ntb_tool and ntb_transport
|
|
The "lock_page_killable()" function waits for exclusive access to the
page lock bit using the WQ_FLAG_EXCLUSIVE bit in the waitqueue entry
set.
That means that if it gets woken up, other waiters may have been
skipped.
That, in turn, means that if it sees the page being unlocked, it *must*
take that lock and return success, even if a lethal signal is also
pending.
So instead of checking for lethal signals first, we need to check for
them after we've checked the actual bit that we were waiting for. Even
if that might then delay the killing of the process.
This matches the order of the old "wait_on_bit_lock()" infrastructure
that the page locking used to use (and is still used in a few other
areas).
Note that if we still return an error after having unsuccessfully tried
to acquire the page lock, that is ok: that means that some other thread
was able to get ahead of us and lock the page, and when that other
thread then unlocks the page, the wakeup event will be repeated. So any
other pending waiters will now get properly woken up.
Fixes: 62906027091f ("mm: add PageWaiters indicating tasks are waiting for a page bit")
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Jan Kara <jack@suse.cz>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Tim Chen and Kan Liang have been battling a customer load that shows
extremely long page wakeup lists. The cause seems to be constant NUMA
migration of a hot page that is shared across a lot of threads, but the
actual root cause for the exact behavior has not been found.
Tim has a patch that batches the wait list traversal at wakeup time, so
that we at least don't get long uninterruptible cases where we traverse
and wake up thousands of processes and get nasty latency spikes. That
is likely 4.14 material, but we're still discussing the page waitqueue
specific parts of it.
In the meantime, I've tried to look at making the page wait queues less
expensive, and failing miserably. If you have thousands of threads
waiting for the same page, it will be painful. We'll need to try to
figure out the NUMA balancing issue some day, in addition to avoiding
the excessive spinlock hold times.
That said, having tried to rewrite the page wait queues, I can at least
fix up some of the braindamage in the current situation. In particular:
(a) we don't want to continue walking the page wait list if the bit
we're waiting for already got set again (which seems to be one of
the patterns of the bad load). That makes no progress and just
causes pointless cache pollution chasing the pointers.
(b) we don't want to put the non-locking waiters always on the front of
the queue, and the locking waiters always on the back. Not only is
that unfair, it means that we wake up thousands of reading threads
that will just end up being blocked by the writer later anyway.
Also add a comment about the layout of 'struct wait_page_key' - there is
an external user of it in the cachefiles code that means that it has to
match the layout of 'struct wait_bit_key' in the two first members. It
so happens to match, because 'struct page *' and 'unsigned long *' end
up having the same values simply because the page flags are the first
member in struct page.
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Christopher Lameter <cl@linux.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
We have a MAX_LFS_FILESIZE macro that is meant to be filled in by
filesystems (and other IO targets) that know they are 64-bit clean and
don't have any 32-bit limits in their IO path.
It turns out that our 32-bit value for that limit was bogus. On 32-bit,
the VM layer is limited by the page cache to only 32-bit index values,
but our logic for that was confusing and actually wrong. We used to
define that value to
(((loff_t)PAGE_SIZE << (BITS_PER_LONG-1))-1)
which is actually odd in several ways: it limits the index to 31 bits,
and then it limits files so that they can't have data in that last byte
of a page that has the highest 31-bit index (ie page index 0x7fffffff).
Neither of those limitations make sense. The index is actually the full
32 bit unsigned value, and we can use that whole full page. So the
maximum size of the file would logically be "PAGE_SIZE << BITS_PER_LONG".
However, we do wan tto avoid the maximum index, because we have code
that iterates over the page indexes, and we don't want that code to
overflow. So the maximum size of a file on a 32-bit host should
actually be one page less than the full 32-bit index.
So the actual limit is ULONG_MAX << PAGE_SHIFT. That means that we will
not actually be using the page of that last index (ULONG_MAX), but we
can grow a file up to that limit.
The wrong value of MAX_LFS_FILESIZE actually caused problems for Doug
Nazar, who was still using a 32-bit host, but with a 9.7TB 2 x RAID5
volume. It turns out that our old MAX_LFS_FILESIZE was 8TiB (well, one
byte less), but the actual true VM limit is one page less than 16TiB.
This was invisible until commit c2a9737f45e2 ("vfs,mm: fix a dead loop
in truncate_inode_pages_range()"), which started applying that
MAX_LFS_FILESIZE limit to block devices too.
NOTE! On 64-bit, the page index isn't a limiter at all, and the limit is
actually just the offset type itself (loff_t), which is signed. But for
clarity, on 64-bit, just use the maximum signed value, and don't make
people have to count the number of 'f' characters in the hex constant.
So just use LLONG_MAX for the 64-bit case. That was what the value had
been before too, just written out as a hex constant.
Fixes: c2a9737f45e2 ("vfs,mm: fix a dead loop in truncate_inode_pages_range()")
Reported-and-tested-by: Doug Nazar <nazard@nazar.ca>
Cc: Andreas Dilger <adilger@dilger.ca>
Cc: Mark Fasheh <mfasheh@versity.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Dave Kleikamp <shaggy@kernel.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull input fixes from Dmitry Torokhov:
- a tweak to the IBM Trackpoint driver that helps recognizing
trackpoints on never Lenovo Carbons
- a fix to the ALPS driver solving scroll issues on some Dells
- yet another ACPI ID has been added to Elan I2C toucpad driver
- quieted diagnostic message in soc_button_array driver
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: ALPS - fix two-finger scroll breakage in right side on ALPS touchpad
Input: soc_button_array - silence -ENOENT error on Dell XPS13 9365
Input: trackpoint - add new trackpoint firmware ID
Input: elan_i2c - add ELAN0602 ACPI ID to support Lenovo Yoga310
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI fix from Bjorn Helgaas:
"Remove needlessly alarming MSI affinity warning (this is not actually
a bug fix, but the warning prompts unnecessary bug reports)"
* tag 'pci-v4.13-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
PCI/MSI: Don't warn when irq_create_affinity_masks() returns NULL
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
"Two fixes: one for an ldt_struct handling bug and a cherry-picked
objtool fix"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Fix use-after-free of ldt_struct
objtool: Fix '-mtune=atom' decoding support in objtool 2.0
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fix from Ingo Molnar:
"Fix a timer granularity handling race+bug, which would manifest itself
by spuriously increasing timeouts of some timers (from 1 jiffy to ~500
jiffies in the worst case measured) in certain nohz states"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timers: Fix excessive granularity of new timers after a nohz idle
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fix from Ingo Molnar:
"A single fix to not allow nonsensical event groups that result in
kernel warnings"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix group {cpu,task} validation
|
|
Merge misc fixes from Andrew Morton:
"6 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm/memblock.c: reversed logic in memblock_discard()
fork: fix incorrect fput of ->exe_file causing use-after-free
mm/madvise.c: fix freeing of locked page with MADV_FREE
dax: fix deadlock due to misaligned PMD faults
mm, shmem: fix handling /sys/kernel/mm/transparent_hugepage/shmem_enabled
PM/hibernate: touch NMI watchdog when creating snapshot
|
|
Pull Paolo Bonzini:
"Bugfixes for x86, PPC and s390"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: PPC: Book3S: Fix race and leak in kvm_vm_ioctl_create_spapr_tce()
KVM, pkeys: do not use PKRU value in vcpu->arch.guest_fpu.state
KVM: x86: simplify handling of PKRU
KVM: x86: block guest protection keys unless the host has them enabled
KVM: PPC: Book3S HV: Add missing barriers to XIVE code and document them
KVM: PPC: Book3S HV: Workaround POWER9 DD1.0 bug causing IPB bit loss
KVM: PPC: Book3S HV: Use msgsync with hypervisor doorbells on POWER9
KVM: s390: sthyi: fix specification exception detection
KVM: s390: sthyi: fix sthyi inline assembly
|
|
Pull virtio fixes from Michael Tsirkin:
"Fixes two obvious bugs in virtio pci"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
virtio_pci: fix cpu affinity support
virtio_blk: fix incorrect message when disk is resized
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fix from Michael Ellerman:
"Just one fix, to add a barrier in the switch_mm() code to make sure
the mm cpumask update is ordered vs the MMU starting to load
translations. As far as we know no one's actually hit the bug, but
that's just luck.
Thanks to Benjamin Herrenschmidt, Nicholas Piggin"
* tag 'powerpc-4.13-8' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/mm: Ensure cpumask update is ordered
|
|
Pull nfsd fixes from Bruce Fields:
"Two nfsd bugfixes, neither 4.13 regressions, but both potentially
serious"
* tag 'nfsd-4.13-2' of git://linux-nfs.org/~bfields/linux:
net: sunrpc: svcsock: fix NULL-pointer exception
nfsd: Limit end of page list when decoding NFSv4 WRITE
|
|
git://git.samba.org/sfrench/cifs-2.6
Pull cifs fixes from Steve French:
"Some bug fixes for stable for cifs"
* tag 'cifs-fixes-for-4.13-rc6-and-stable' of git://git.samba.org/sfrench/cifs-2.6:
cifs: return ENAMETOOLONG for overlong names in cifs_open()/cifs_lookup()
cifs: Fix df output for users with quota limits
|
|
Pull MTD fixes from Brian Norris:
"Two fixes - one for a 4.13 regression, and the other for an older one:
- Atmel NAND: since we started utilizing ONFI timings, we found that
we were being too restrict at rejecting them, partly due to
discrepancies in ONFI 4.0 and earlier versions. Relax the
restriction to keep these platforms booting. This is a 4.13-rc1
regression.
- nandsim: repeated probe/removal may not work after a failed init,
because we didn't free up our debugfs files properly on the failure
path. This has been around since 3.8, but it's nice to get this
fixed now in a nice easy patch that can target -stable, since
there's already refactoring work (that also fixes the issue)
targeted for the next merge window"
* tag 'for-linus-20170825' of git://git.infradead.org/linux-mtd:
mtd: nand: atmel: Relax tADL_min constraint
mtd: nandsim: remove debugfs entries in error path
|
|
Pull block fixes from Jens Axboe:
"A small batch of fixes that should be included for the 4.13 release.
This contains:
- Revert of the 4k loop blocksize support. Even with a recent batch
of 4 fixes, we're still not really happy with it. Rather than be
stuck with an API issue, let's revert it and get it right for 4.14.
- Trivial patch from Bart, adding a few flags to the blk-mq debugfs
exports that were added in this release, but not to the debugfs
parts.
- Regression fix for bsg, fixing a potential kernel panic. From
Benjamin.
- Tweak for the blk throttling, improving how we account discards.
From Shaohua"
* 'for-linus' of git://git.kernel.dk/linux-block:
blk-mq-debugfs: Add names for recently added flags
bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer
Revert "loop: support 4k physical blocksize"
blk-throttle: cap discard request size
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c fixes from Wolfram Sang:
"I2C has some bugfixes for you: mainly Jarkko fixed up a few things in
the designware driver regarding the new slave mode. But Ulf also fixed
a long-standing and now agreed suspend problem. Plus, some simple
stuff which nonetheless needs fixing"
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: designware: Fix runtime PM for I2C slave mode
i2c: designware: Remove needless pm_runtime_put_noidle() call
i2c: aspeed: fixed potential null pointer dereference
i2c: simtec: use release_mem_region instead of release_resource
i2c: core: Make comment about I2C table requirement to reflect the code
i2c: designware: Fix standard mode speed when configuring the slave mode
i2c: designware: Fix oops from i2c_dw_irq_handler_slave
i2c: designware: Fix system suspend
|
|
irq_create_affinity_masks() can return NULL on non-SMP systems, when there
are not enough "free" vectors available to spread, or if memory allocation
for the CPU masks fails. Only the allocation failure is of interest, and
even then the system will work just fine except for non-optimally spread
vectors. Thus remove the warnings.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: David S. Miller <davem@davemloft.net>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc
Pull MMC fix from Ulf Hansson:
"MMC core: don't return error code R1_OUT_OF_RANGE for open-ending mode"
* tag 'mmc-v4.13-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
mmc: block: prevent propagating R1_OUT_OF_RANGE for open-ending mode
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"We're keeping in a good shape, this batch contains just a few small
fixes (a regression fix for ASoC rt5677 codec, NULL dereference and
error-path fixes in firewire, and a corner-case ioctl error fix for
user TLV), as well as usual quirks for USB-audio and HD-audio"
* tag 'sound-4.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ASoC: rt5677: Reintroduce I2C device IDs
ALSA: hda - Add stereo mic quirk for Lenovo G50-70 (17aa:3978)
ALSA: core: Fix unexpected error at replacing user TLV
ALSA: usb-audio: Add delay quirk for H650e/Jabra 550a USB headsets
ALSA: firewire-motu: destroy stream data surely at failure of card initialization
ALSA: firewire: fix NULL pointer dereference when releasing uninitialized data of iso-resource
|
|
git://git.infradead.org/users/vkoul/slave-dma
Pull dmaengine fix from Vinod Koul:
"A single fix for tegra210-adma driver to check of_irq_get() error"
* tag 'dmaengine-fix-4.13-rc7' of git://git.infradead.org/users/vkoul/slave-dma:
dmaengine: tegra210-adma: fix of_irq_get() error check
|
|
git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
"Fixes for rc7, nothing too crazy, some core, i915, and sunxi fixes,
Intel CI has been responsible for some of these fixes being required"
* tag 'drm-fixes-for-v4.13-rc7' of git://people.freedesktop.org/~airlied/linux:
drm/i915/gvt: Fix the kernel null pointer error
drm: Release driver tracking before making the object available again
drm/i915: Clear lost context-switch interrupts across reset
drm/i915/bxt: use NULL for GPIO connection ID
drm/i915/cnl: Fix LSPCON support.
drm/i915/vbt: ignore extraneous child devices for a port
drm/i915: Initialize 'data' in intel_dsi_dcs_backlight.c
drm/atomic: If the atomic check fails, return its value first
drm/atomic: Handle -EDEADLK with out-fences correctly
drm: Fix framebuffer leak
drm/imx: ipuv3-plane: fix YUV framebuffer scanout on the base plane
gpu: ipu-v3: add DRM dependency
drm/rockchip: Fix suspend crash when drm is not bound
drm/sun4i: Implement drm_driver lastclose to restore fbdev console
|
|
In recently introduced memblock_discard() there is a reversed logic bug.
Memory is freed of static array instead of dynamically allocated one.
Link: http://lkml.kernel.org/r/1503511441-95478-2-git-send-email-pasha.tatashin@oracle.com
Fixes: 3010f876500f ("mm: discard memblock data later")
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reported-by: Woody Suwalski <terraluna977@gmail.com>
Tested-by: Woody Suwalski <terraluna977@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Commit 7c051267931a ("mm, fork: make dup_mmap wait for mmap_sem for
write killable") made it possible to kill a forking task while it is
waiting to acquire its ->mmap_sem for write, in dup_mmap().
However, it was overlooked that this introduced an new error path before
a reference is taken on the mm_struct's ->exe_file. Since the
->exe_file of the new mm_struct was already set to the old ->exe_file by
the memcpy() in dup_mm(), it was possible for the mmput() in the error
path of dup_mm() to drop a reference to ->exe_file which was never
taken.
This caused the struct file to later be freed prematurely.
Fix it by updating mm_init() to NULL out the ->exe_file, in the same
place it clears other things like the list of mmaps.
This bug was found by syzkaller. It can be reproduced using the
following C program:
#define _GNU_SOURCE
#include <pthread.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <sys/syscall.h>
#include <sys/wait.h>
#include <unistd.h>
static void *mmap_thread(void *_arg)
{
for (;;) {
mmap(NULL, 0x1000000, PROT_READ,
MAP_POPULATE|MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
}
}
static void *fork_thread(void *_arg)
{
usleep(rand() % 10000);
fork();
}
int main(void)
{
fork();
fork();
fork();
for (;;) {
if (fork() == 0) {
pthread_t t;
pthread_create(&t, NULL, mmap_thread, NULL);
pthread_create(&t, NULL, fork_thread, NULL);
usleep(rand() % 10000);
syscall(__NR_exit_group, 0);
}
wait(NULL);
}
}
No special kernel config options are needed. It usually causes a NULL
pointer dereference in __remove_shared_vm_struct() during exit, or in
dup_mmap() (which is usually inlined into copy_process()) during fork.
Both are due to a vm_area_struct's ->vm_file being used after it's
already been freed.
Google Bug Id: 64772007
Link: http://lkml.kernel.org/r/20170823211408.31198-1-ebiggers3@gmail.com
Fixes: 7c051267931a ("mm, fork: make dup_mmap wait for mmap_sem for write killable")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org> [v4.7+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
If madvise(..., MADV_FREE) split a transparent hugepage, it called
put_page() before unlock_page().
This was wrong because put_page() can free the page, e.g. if a
concurrent madvise(..., MADV_DONTNEED) has removed it from the memory
mapping. put_page() then rightfully complained about freeing a locked
page.
Fix this by moving the unlock_page() before put_page().
This bug was found by syzkaller, which encountered the following splat:
BUG: Bad page state in process syzkaller412798 pfn:1bd800
page:ffffea0006f60000 count:0 mapcount:0 mapping: (null) index:0x20a00
flags: 0x200000000040019(locked|uptodate|dirty|swapbacked)
raw: 0200000000040019 0000000000000000 0000000000020a00 00000000ffffffff
raw: ffffea0006f60020 ffffea0006f60020 0000000000000000 0000000000000000
page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set
bad because of flags: 0x1(locked)
Modules linked in:
CPU: 1 PID: 3037 Comm: syzkaller412798 Not tainted 4.13.0-rc5+ #35
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:16 [inline]
dump_stack+0x194/0x257 lib/dump_stack.c:52
bad_page+0x230/0x2b0 mm/page_alloc.c:565
free_pages_check_bad+0x1f0/0x2e0 mm/page_alloc.c:943
free_pages_check mm/page_alloc.c:952 [inline]
free_pages_prepare mm/page_alloc.c:1043 [inline]
free_pcp_prepare mm/page_alloc.c:1068 [inline]
free_hot_cold_page+0x8cf/0x12b0 mm/page_alloc.c:2584
__put_single_page mm/swap.c:79 [inline]
__put_page+0xfb/0x160 mm/swap.c:113
put_page include/linux/mm.h:814 [inline]
madvise_free_pte_range+0x137a/0x1ec0 mm/madvise.c:371
walk_pmd_range mm/pagewalk.c:50 [inline]
walk_pud_range mm/pagewalk.c:108 [inline]
walk_p4d_range mm/pagewalk.c:134 [inline]
walk_pgd_range mm/pagewalk.c:160 [inline]
__walk_page_range+0xc3a/0x1450 mm/pagewalk.c:249
walk_page_range+0x200/0x470 mm/pagewalk.c:326
madvise_free_page_range.isra.9+0x17d/0x230 mm/madvise.c:444
madvise_free_single_vma+0x353/0x580 mm/madvise.c:471
madvise_dontneed_free mm/madvise.c:555 [inline]
madvise_vma mm/madvise.c:664 [inline]
SYSC_madvise mm/madvise.c:832 [inline]
SyS_madvise+0x7d3/0x13c0 mm/madvise.c:760
entry_SYSCALL_64_fastpath+0x1f/0xbe
Here is a C reproducer:
#define _GNU_SOURCE
#include <pthread.h>
#include <sys/mman.h>
#include <unistd.h>
#define MADV_FREE 8
#define PAGE_SIZE 4096
static void *mapping;
static const size_t mapping_size = 0x1000000;
static void *madvise_thrproc(void *arg)
{
madvise(mapping, mapping_size, (long)arg);
}
int main(void)
{
pthread_t t[2];
for (;;) {
mapping = mmap(NULL, mapping_size, PROT_WRITE,
MAP_POPULATE|MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
munmap(mapping + mapping_size / 2, PAGE_SIZE);
pthread_create(&t[0], 0, madvise_thrproc, (void*)MADV_DONTNEED);
pthread_create(&t[1], 0, madvise_thrproc, (void*)MADV_FREE);
pthread_join(t[0], NULL);
pthread_join(t[1], NULL);
munmap(mapping, mapping_size);
}
}
Note: to see the splat, CONFIG_TRANSPARENT_HUGEPAGE=y and
CONFIG_DEBUG_VM=y are needed.
Google Bug Id: 64696096
Link: http://lkml.kernel.org/r/20170823205235.132061-1-ebiggers3@gmail.com
Fixes: 854e9ed09ded ("mm: support madvise(MADV_FREE)")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: <stable@vger.kernel.org> [v4.5+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
In DAX there are two separate places where the 2MiB range of a PMD is
defined.
The first is in the page tables, where a PMD mapping inserted for a
given address spans from (vmf->address & PMD_MASK) to ((vmf->address &
PMD_MASK) + PMD_SIZE - 1). That is, from the 2MiB boundary below the
address to the 2MiB boundary above the address.
So, for example, a fault at address 3MiB (0x30 0000) falls within the
PMD that ranges from 2MiB (0x20 0000) to 4MiB (0x40 0000).
The second PMD range is in the mapping->page_tree, where a given file
offset is covered by a radix tree entry that spans from one 2MiB aligned
file offset to another 2MiB aligned file offset.
So, for example, the file offset for 3MiB (pgoff 768) falls within the
PMD range for the order 9 radix tree entry that ranges from 2MiB (pgoff
512) to 4MiB (pgoff 1024).
This system works so long as the addresses and file offsets for a given
mapping both have the same offsets relative to the start of each PMD.
Consider the case where the starting address for a given file isn't 2MiB
aligned - say our faulting address is 3 MiB (0x30 0000), but that
corresponds to the beginning of our file (pgoff 0). Now all the PMDs in
the mapping are misaligned so that the 2MiB range defined in the page
tables never matches up with the 2MiB range defined in the radix tree.
The current code notices this case for DAX faults to storage with the
following test in dax_pmd_insert_mapping():
if (pfn_t_to_pfn(pfn) & PG_PMD_COLOUR)
goto unlock_fallback;
This test makes sure that the pfn we get from the driver is 2MiB
aligned, and relies on the assumption that the 2MiB alignment of the pfn
we get back from the driver matches the 2MiB alignment of the faulting
address.
However, faults to holes were not checked and we could hit the problem
described above.
This was reported in response to the NVML nvml/src/test/pmempool_sync
TEST5:
$ cd nvml/src/test/pmempool_sync
$ make TEST5
You can grab NVML here:
https://github.com/pmem/nvml/
The dmesg warning you see when you hit this error is:
WARNING: CPU: 13 PID: 2900 at fs/dax.c:641 dax_insert_mapping_entry+0x2df/0x310
Where we notice in dax_insert_mapping_entry() that the radix tree entry
we are about to replace doesn't match the locked entry that we had
previously inserted into the tree. This happens because the initial
insertion was done in grab_mapping_entry() using a pgoff calculated from
the faulting address (vmf->address), and the replacement in
dax_pmd_load_hole() => dax_insert_mapping_entry() is done using
vmf->pgoff.
In our failure case those two page offsets (one calculated from
vmf->address, one using vmf->pgoff) point to different order 9 radix
tree entries.
This failure case can result in a deadlock because the radix tree unlock
also happens on the pgoff calculated from vmf->address. This means that
the locked radix tree entry that we swapped in to the tree in
dax_insert_mapping_entry() using vmf->pgoff is never unlocked, so all
future faults to that 2MiB range will block forever.
Fix this by validating that the faulting address's PMD offset matches
the PMD offset from the start of the file. This check is done at the
very beginning of the fault and covers faults that would have mapped to
storage as well as faults to holes. I left the COLOUR check in
dax_pmd_insert_mapping() in place in case we ever hit the insanity
condition where the alignment of the pfn we get from the driver doesn't
match the alignment of the userspace address.
Link: http://lkml.kernel.org/r/20170822222436.18926-1-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reported-by: "Slusarz, Marcin" <marcin.slusarz@intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
/sys/kernel/mm/transparent_hugepage/shmem_enabled controls if we want
to allocate huge pages when allocate pages for private in-kernel shmem
mount.
Unfortunately, as Dan noticed, I've screwed it up and the only way to
make kernel allocate huge page for the mount is to use "force" there.
All other values will be effectively ignored.
Link: http://lkml.kernel.org/r/20170822144254.66431-1-kirill.shutemov@linux.intel.com
Fixes: 5a6e75f8110c ("shmem: prepare huge= mount option and sysfs knob")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable <stable@vger.kernel.org> [4.8+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
There is a problem that when counting the pages for creating the
hibernation snapshot will take significant amount of time, especially on
system with large memory. Since the counting job is performed with irq
disabled, this might lead to NMI lockup. The following warning were
found on a system with 1.5TB DRAM:
Freezing user space processes ... (elapsed 0.002 seconds) done.
OOM killer disabled.
PM: Preallocating image memory...
NMI watchdog: Watchdog detected hard LOCKUP on cpu 27
CPU: 27 PID: 3128 Comm: systemd-sleep Not tainted 4.13.0-0.rc2.git0.1.fc27.x86_64 #1
task: ffff9f01971ac000 task.stack: ffffb1a3f325c000
RIP: 0010:memory_bm_find_bit+0xf4/0x100
Call Trace:
swsusp_set_page_free+0x2b/0x30
mark_free_pages+0x147/0x1c0
count_data_pages+0x41/0xa0
hibernate_preallocate_memory+0x80/0x450
hibernation_snapshot+0x58/0x410
hibernate+0x17c/0x310
state_store+0xdf/0xf0
kobj_attr_store+0xf/0x20
sysfs_kf_write+0x37/0x40
kernfs_fop_write+0x11c/0x1a0
__vfs_write+0x37/0x170
vfs_write+0xb1/0x1a0
SyS_write+0x55/0xc0
entry_SYSCALL_64_fastpath+0x1a/0xa5
...
done (allocated 6590003 pages)
PM: Allocated 26360012 kbytes in 19.89 seconds (1325.28 MB/s)
It has taken nearly 20 seconds(2.10GHz CPU) thus the NMI lockup was
triggered. In case the timeout of the NMI watch dog has been set to 1
second, a safe interval should be 6590003/20 = 320k pages in theory.
However there might also be some platforms running at a lower frequency,
so feed the watchdog every 100k pages.
[yu.c.chen@intel.com: simplification]
Link: http://lkml.kernel.org/r/1503460079-29721-1-git-send-email-yu.c.chen@intel.com
[yu.c.chen@intel.com: use interval of 128k instead of 100k to avoid modulus]
Link: http://lkml.kernel.org/r/1503328098-5120-1-git-send-email-yu.c.chen@intel.com
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Reported-by: Jan Filipcewicz <jan.filipcewicz@intel.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Michal Hocko <mhocko@suse.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Len Brown <lenb@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Commit 0b0f9dc5 ("Revert "virtio_pci: use shared interrupts for
virtqueues"") removed the adjustment of the pre_vectors for the virtio
MSI-X vector allocation which was added in commit fb5e31d9 ("virtio:
allow drivers to request IRQ affinity when creating VQs"). This will
lead to an incorrect assignment of MSI-X vectors, and potential
deadlocks when offlining cpus.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Fixes: 0b0f9dc5 ("Revert "virtio_pci: use shared interrupts for virtqueues")
Reported-by: YASUAKI ISHIMATSU <yasu.isimatu@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
|
|
The message printed on disk resize is incorrect. The following is
printed when resizing to 2 GiB:
$ truncate -s 1G test.img
$ qemu -device virtio-blk-pci,logical_block_size=4096,...
(qemu) block_resize drive1 2G
virtio_blk virtio0: new size: 4194304 4096-byte logical blocks (17.2 GB/16.0 GiB)
The virtio_blk capacity config field is in 512-byte sector units
regardless of logical_block_size as per the VIRTIO specification.
Therefore the message should read:
virtio_blk virtio0: new size: 524288 4096-byte logical blocks (2.15 GB/2.0 GiB)
Note that this only affects the printed message. Thankfully the actual
block device has the correct size because the block layer expects
capacity in sectors.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
|
|
The symbolic constants QUEUE_FLAG_SCSI_PASSTHROUGH, QUEUE_FLAG_QUIESCED
and REQ_NOWAIT are missing from blk-mq-debugfs.c. Add these to
blk-mq-debugfs.c such that these appear as names in debugfs instead of
as numbers.
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
|
|
Nixiaoming pointed out that there is a memory leak in
kvm_vm_ioctl_create_spapr_tce() if the call to anon_inode_getfd()
fails; the memory allocated for the kvmppc_spapr_tce_table struct
is not freed, and nor are the pages allocated for the iommu
tables. In addition, we have already incremented the process's
count of locked memory pages, and this doesn't get restored on
error.
David Hildenbrand pointed out that there is a race in that the
function checks early on that there is not already an entry in the
stt->iommu_tables list with the same LIOBN, but an entry with the
same LIOBN could get added between then and when the new entry is
added to the list.
This fixes all three problems. To simplify things, we now call
anon_inode_getfd() before placing the new entry in the list. The
check for an existing entry is done while holding the kvm->lock
mutex, immediately before adding the new entry to the list.
Finally, on failure we now call kvmppc_account_memlimit to
decrement the process's count of locked memory pages.
Reported-by: Nixiaoming <nixiaoming@huawei.com>
Reported-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
|
|
Regardless of which events form a group, it does not make sense for the
events to target different tasks and/or CPUs, as this leaves the group
inconsistent and impossible to schedule. The core perf code assumes that
these are consistent across (successfully intialised) groups.
Core perf code only verifies this when moving SW events into a HW
context. Thus, we can violate this requirement for pure SW groups and
pure HW groups, unless the relevant PMU driver happens to perform this
verification itself. These mismatched groups subsequently wreak havoc
elsewhere.
For example, we handle watchpoints as SW events, and reserve watchpoint
HW on a per-CPU basis at pmu::event_init() time to ensure that any event
that is initialised is guaranteed to have a slot at pmu::add() time.
However, the core code only checks the group leader's cpu filter (via
event_filter_match()), and can thus install follower events onto CPUs
violating thier (mismatched) CPU filters, potentially installing them
into a CPU without sufficient reserved slots.
This can be triggered with the below test case, resulting in warnings
from arch backends.
#define _GNU_SOURCE
#include <linux/hw_breakpoint.h>
#include <linux/perf_event.h>
#include <sched.h>
#include <stdio.h>
#include <sys/prctl.h>
#include <sys/syscall.h>
#include <unistd.h>
static int perf_event_open(struct perf_event_attr *attr, pid_t pid, int cpu,
int group_fd, unsigned long flags)
{
return syscall(__NR_perf_event_open, attr, pid, cpu, group_fd, flags);
}
char watched_char;
struct perf_event_attr wp_attr = {
.type = PERF_TYPE_BREAKPOINT,
.bp_type = HW_BREAKPOINT_RW,
.bp_addr = (unsigned long)&watched_char,
.bp_len = 1,
.size = sizeof(wp_attr),
};
int main(int argc, char *argv[])
{
int leader, ret;
cpu_set_t cpus;
/*
* Force use of CPU0 to ensure our CPU0-bound events get scheduled.
*/
CPU_ZERO(&cpus);
CPU_SET(0, &cpus);
ret = sched_setaffinity(0, sizeof(cpus), &cpus);
if (ret) {
printf("Unable to set cpu affinity\n");
return 1;
}
/* open leader event, bound to this task, CPU0 only */
leader = perf_event_open(&wp_attr, 0, 0, -1, 0);
if (leader < 0) {
printf("Couldn't open leader: %d\n", leader);
return 1;
}
/*
* Open a follower event that is bound to the same task, but a
* different CPU. This means that the group should never be possible to
* schedule.
*/
ret = perf_event_open(&wp_attr, 0, 1, leader, 0);
if (ret < 0) {
printf("Couldn't open mismatched follower: %d\n", ret);
return 1;
} else {
printf("Opened leader/follower with mismastched CPUs\n");
}
/*
* Open as many independent events as we can, all bound to the same
* task, CPU0 only.
*/
do {
ret = perf_event_open(&wp_attr, 0, 0, -1, 0);
} while (ret >= 0);
/*
* Force enable/disble all events to trigger the erronoeous
* installation of the follower event.
*/
printf("Opened all events. Toggling..\n");
for (;;) {
prctl(PR_TASK_PERF_EVENTS_DISABLE, 0, 0, 0, 0);
prctl(PR_TASK_PERF_EVENTS_ENABLE, 0, 0, 0, 0);
}
return 0;
}
Fix this by validating this requirement regardless of whether we're
moving events.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Zhou Chengming <zhouchengming1@huawei.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1498142498-15758-1-git-send-email-mark.rutland@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
The following commit:
39a0526fb3f7 ("x86/mm: Factor out LDT init from context init")
renamed init_new_context() to init_new_context_ldt() and added a new
init_new_context() which calls init_new_context_ldt(). However, the
error code of init_new_context_ldt() was ignored. Consequently, if a
memory allocation in alloc_ldt_struct() failed during a fork(), the
->context.ldt of the new task remained the same as that of the old task
(due to the memcpy() in dup_mm()). ldt_struct's are not intended to be
shared, so a use-after-free occurred after one task exited.
Fix the bug by making init_new_context() pass through the error code of
init_new_context_ldt().
This bug was found by syzkaller, which encountered the following splat:
BUG: KASAN: use-after-free in free_ldt_struct.part.2+0x10a/0x150 arch/x86/kernel/ldt.c:116
Read of size 4 at addr ffff88006d2cb7c8 by task kworker/u9:0/3710
CPU: 1 PID: 3710 Comm: kworker/u9:0 Not tainted 4.13.0-rc4-next-20170811 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:16 [inline]
dump_stack+0x194/0x257 lib/dump_stack.c:52
print_address_description+0x73/0x250 mm/kasan/report.c:252
kasan_report_error mm/kasan/report.c:351 [inline]
kasan_report+0x24e/0x340 mm/kasan/report.c:409
__asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:429
free_ldt_struct.part.2+0x10a/0x150 arch/x86/kernel/ldt.c:116
free_ldt_struct arch/x86/kernel/ldt.c:173 [inline]
destroy_context_ldt+0x60/0x80 arch/x86/kernel/ldt.c:171
destroy_context arch/x86/include/asm/mmu_context.h:157 [inline]
__mmdrop+0xe9/0x530 kernel/fork.c:889
mmdrop include/linux/sched/mm.h:42 [inline]
exec_mmap fs/exec.c:1061 [inline]
flush_old_exec+0x173c/0x1ff0 fs/exec.c:1291
load_elf_binary+0x81f/0x4ba0 fs/binfmt_elf.c:855
search_binary_handler+0x142/0x6b0 fs/exec.c:1652
exec_binprm fs/exec.c:1694 [inline]
do_execveat_common.isra.33+0x1746/0x22e0 fs/exec.c:1816
do_execve+0x31/0x40 fs/exec.c:1860
call_usermodehelper_exec_async+0x457/0x8f0 kernel/umh.c:100
ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431
Allocated by task 3700:
save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
save_stack+0x43/0xd0 mm/kasan/kasan.c:447
set_track mm/kasan/kasan.c:459 [inline]
kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
kmem_cache_alloc_trace+0x136/0x750 mm/slab.c:3627
kmalloc include/linux/slab.h:493 [inline]
alloc_ldt_struct+0x52/0x140 arch/x86/kernel/ldt.c:67
write_ldt+0x7b7/0xab0 arch/x86/kernel/ldt.c:277
sys_modify_ldt+0x1ef/0x240 arch/x86/kernel/ldt.c:307
entry_SYSCALL_64_fastpath+0x1f/0xbe
Freed by task 3700:
save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
save_stack+0x43/0xd0 mm/kasan/kasan.c:447
set_track mm/kasan/kasan.c:459 [inline]
kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524
__cache_free mm/slab.c:3503 [inline]
kfree+0xca/0x250 mm/slab.c:3820
free_ldt_struct.part.2+0xdd/0x150 arch/x86/kernel/ldt.c:121
free_ldt_struct arch/x86/kernel/ldt.c:173 [inline]
destroy_context_ldt+0x60/0x80 arch/x86/kernel/ldt.c:171
destroy_context arch/x86/include/asm/mmu_context.h:157 [inline]
__mmdrop+0xe9/0x530 kernel/fork.c:889
mmdrop include/linux/sched/mm.h:42 [inline]
__mmput kernel/fork.c:916 [inline]
mmput+0x541/0x6e0 kernel/fork.c:927
copy_process.part.36+0x22e1/0x4af0 kernel/fork.c:1931
copy_process kernel/fork.c:1546 [inline]
_do_fork+0x1ef/0xfb0 kernel/fork.c:2025
SYSC_clone kernel/fork.c:2135 [inline]
SyS_clone+0x37/0x50 kernel/fork.c:2129
do_syscall_64+0x26c/0x8c0 arch/x86/entry/common.c:287
return_from_SYSCALL_64+0x0/0x7a
Here is a C reproducer:
#include <asm/ldt.h>
#include <pthread.h>
#include <signal.h>
#include <stdlib.h>
#include <sys/syscall.h>
#include <sys/wait.h>
#include <unistd.h>
static void *fork_thread(void *_arg)
{
fork();
}
int main(void)
{
struct user_desc desc = { .entry_number = 8191 };
syscall(__NR_modify_ldt, 1, &desc, sizeof(desc));
for (;;) {
if (fork() == 0) {
pthread_t t;
srand(getpid());
pthread_create(&t, NULL, fork_thread, NULL);
usleep(rand() % 10000);
syscall(__NR_exit_group, 0);
}
wait(NULL);
}
}
Note: the reproducer takes advantage of the fact that alloc_ldt_struct()
may use vmalloc() to allocate a large ->entries array, and after
commit:
5d17a73a2ebe ("vmalloc: back off when the current task is killed")
it is possible for userspace to fail a task's vmalloc() by
sending a fatal signal, e.g. via exit_group(). It would be more
difficult to reproduce this bug on kernels without that commit.
This bug only affected kernels with CONFIG_MODIFY_LDT_SYSCALL=y.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: <stable@vger.kernel.org> [v4.6+]
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: Christoph Hellwig <hch@lst.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Fixes: 39a0526fb3f7 ("x86/mm: Factor out LDT init from context init")
Link: http://lkml.kernel.org/r/20170824175029.76040-1-ebiggers3@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
The host pkru is restored right after vcpu exit (commit 1be0e61), so
KVM_GET_XSAVE will return the host PKRU value instead. Fix this by
using the guest PKRU explicitly in fill_xsave and load_xsave. This
part is based on a patch by Junkang Fu.
The host PKRU data may also not match the value in vcpu->arch.guest_fpu.state,
because it could have been changed by userspace since the last time
it was saved, so skip loading it in kvm_load_guest_fpu.
Reported-by: Junkang Fu <junkang.fjk@alibaba-inc.com>
Cc: Yang Zhang <zy107165@alibaba-inc.com>
Fixes: 1be0e61c1f255faaeab04a390e00c8b9b9042870
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
|
|
Move it to struct kvm_arch_vcpu, replacing guest_pkru_valid with a
simple comparison against the host value of the register. The write of
PKRU in addition can be skipped if the guest has not enabled the feature.
Once we do this, we need not test OSPKE in the host anymore, because
guest_CR4.PKE=1 implies host_CR4.PKE=1.
The static PKU test is kept to elide the code on older CPUs.
Suggested-by: Yang Zhang <zy107165@alibaba-inc.com>
Fixes: 1be0e61c1f255faaeab04a390e00c8b9b9042870
Cc: stable@vger.kernel.org
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
|
|
If the host has protection keys disabled, we cannot read and write the
guest PKRU---RDPKRU and WRPKRU fail with #GP(0) if CR4.PKE=0. Block
the PKU cpuid bit in that case.
This ensures that guest_CR4.PKE=1 implies host_CR4.PKE=1.
Fixes: 1be0e61c1f255faaeab04a390e00c8b9b9042870
Cc: stable@vger.kernel.org
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
|