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2019-11-16x86/bugs: Add ITLB_MULTIHIT bug infrastructureVineela Tummalapalli1-0/+8
commit db4d30fbb71b47e4ecb11c4efa5d8aad4b03dfae upstream. Some processors may incur a machine check error possibly resulting in an unrecoverable CPU lockup when an instruction fetch encounters a TLB multi-hit in the instruction TLB. This can occur when the page size is changed along with either the physical address or cache type. The relevant erratum can be found here: https://bugzilla.kernel.org/show_bug.cgi?id=205195 There are other processors affected for which the erratum does not fully disclose the impact. This issue affects both bare-metal x86 page tables and EPT. It can be mitigated by either eliminating the use of large pages or by using careful TLB invalidations when changing the page size in the page tables. Just like Spectre, Meltdown, L1TF and MDS, a new bit has been allocated in MSR_IA32_ARCH_CAPABILITIES (PSCHANGE_MC_NO) and will be set on CPUs which are mitigated against this issue. Signed-off-by: Vineela Tummalapalli <vineela.tummalapalli@intel.com> Co-developed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> [bwh: Backported to 4.4: - No support for X86_VENDOR_HYGON, ATOM_AIRMONT_NP - Adjust context, indentation] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-16x86/speculation/taa: Add sysfs reporting for TSX Async AbortPawan Gupta1-0/+9
commit 6608b45ac5ecb56f9e171252229c39580cc85f0f upstream. Add the sysfs reporting file for TSX Async Abort. It exposes the vulnerability and the mitigation state similar to the existing files for the other hardware vulnerabilities. Sysfs file path is: /sys/devices/system/cpu/vulnerabilities/tsx_async_abort Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Neelima Krishnan <neelima.krishnan@intel.com> Reviewed-by: Mark Gross <mgross@linux.intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-29cpufreq: Avoid cpufreq_suspend() deadlock on system shutdownRafael J. Wysocki1-0/+3
commit 65650b35133ff20f0c9ef0abd5c3c66dbce3ae57 upstream. It is incorrect to set the cpufreq syscore shutdown callback pointer to cpufreq_suspend(), because that function cannot be run in the syscore stage of system shutdown for two reasons: (a) it may attempt to carry out actions depending on devices that have already been shut down at that point and (b) the RCU synchronization carried out by it may not be able to make progress then. The latter issue has been present since commit 45975c7d21a1 ("rcu: Define RCU-sched API in terms of RCU for Tree RCU PREEMPT builds"), but the former one has been there since commit 90de2a4aa9f3 ("cpufreq: suspend cpufreq governors on shutdown") regardless. Fix that by dropping cpufreq_syscore_ops altogether and making device_shutdown() call cpufreq_suspend() directly before shutting down devices, which is along the lines of what system-wide power management does. Fixes: 45975c7d21a1 ("rcu: Define RCU-sched API in terms of RCU for Tree RCU PREEMPT builds") Fixes: 90de2a4aa9f3 ("cpufreq: suspend cpufreq governors on shutdown") Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Tested-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: 4.0+ <stable@vger.kernel.org> # 4.0+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-05base: soc: Export soc_device_register/unregister APIsVinod Koul1-0/+2
[ Upstream commit f7ccc7a397cf2ef64aebb2f726970b93203858d2 ] Qcom Socinfo driver can be built as a module, so export these two APIs. Tested-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Vaishali Thakkar <vaishali.thakkar@linaro.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-09-21driver core: Fix use-after-free and double free on glue directoryMuchun Song1-1/+52
commit ac43432cb1f5c2950408534987e57c2071e24d8f upstream. There is a race condition between removing glue directory and adding a new device under the glue dir. It can be reproduced in following test: CPU1: CPU2: device_add() get_device_parent() class_dir_create_and_add() kobject_add_internal() create_dir() // create glue_dir device_add() get_device_parent() kobject_get() // get glue_dir device_del() cleanup_glue_dir() kobject_del(glue_dir) kobject_add() kobject_add_internal() create_dir() // in glue_dir sysfs_create_dir_ns() kernfs_create_dir_ns(sd) sysfs_remove_dir() // glue_dir->sd=NULL sysfs_put() // free glue_dir->sd // sd is freed kernfs_new_node(sd) kernfs_get(glue_dir) kernfs_add_one() kernfs_put() Before CPU1 remove last child device under glue dir, if CPU2 add a new device under glue dir, the glue_dir kobject reference count will be increase to 2 via kobject_get() in get_device_parent(). And CPU2 has been called kernfs_create_dir_ns(), but not call kernfs_new_node(). Meanwhile, CPU1 call sysfs_remove_dir() and sysfs_put(). This result in glue_dir->sd is freed and it's reference count will be 0. Then CPU2 call kernfs_get(glue_dir) will trigger a warning in kernfs_get() and increase it's reference count to 1. Because glue_dir->sd is freed by CPU1, the next call kernfs_add_one() by CPU2 will fail(This is also use-after-free) and call kernfs_put() to decrease reference count. Because the reference count is decremented to 0, it will also call kmem_cache_free() to free the glue_dir->sd again. This will result in double free. In order to avoid this happening, we also should make sure that kernfs_node for glue_dir is released in CPU1 only when refcount for glue_dir kobj is 1 to fix this race. The following calltrace is captured in kernel 4.14 with the following patch applied: commit 726e41097920 ("drivers: core: Remove glue dirs from sysfs earlier") -------------------------------------------------------------------------- [ 3.633703] WARNING: CPU: 4 PID: 513 at .../fs/kernfs/dir.c:494 Here is WARN_ON(!atomic_read(&kn->count) in kernfs_get(). .... [ 3.633986] Call trace: [ 3.633991] kernfs_create_dir_ns+0xa8/0xb0 [ 3.633994] sysfs_create_dir_ns+0x54/0xe8 [ 3.634001] kobject_add_internal+0x22c/0x3f0 [ 3.634005] kobject_add+0xe4/0x118 [ 3.634011] device_add+0x200/0x870 [ 3.634017] _request_firmware+0x958/0xc38 [ 3.634020] request_firmware_into_buf+0x4c/0x70 .... [ 3.634064] kernel BUG at .../mm/slub.c:294! Here is BUG_ON(object == fp) in set_freepointer(). .... [ 3.634346] Call trace: [ 3.634351] kmem_cache_free+0x504/0x6b8 [ 3.634355] kernfs_put+0x14c/0x1d8 [ 3.634359] kernfs_create_dir_ns+0x88/0xb0 [ 3.634362] sysfs_create_dir_ns+0x54/0xe8 [ 3.634366] kobject_add_internal+0x22c/0x3f0 [ 3.634370] kobject_add+0xe4/0x118 [ 3.634374] device_add+0x200/0x870 [ 3.634378] _request_firmware+0x958/0xc38 [ 3.634381] request_firmware_into_buf+0x4c/0x70 -------------------------------------------------------------------------- Fixes: 726e41097920 ("drivers: core: Remove glue dirs from sysfs earlier") Signed-off-by: Muchun Song <smuchun@gmail.com> Reviewed-by: Mukesh Ojha <mojha@codeaurora.org> Signed-off-by: Prateek Sood <prsood@codeaurora.org> Link: https://lore.kernel.org/r/20190727032122.24639-1-smuchun@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-04regmap: fix bulk writes on paged registersSrinivas Kandagatla1-0/+2
[ Upstream commit db057679de3e9e6a03c1bcd5aee09b0d25fd9f5b ] On buses like SlimBus and SoundWire which does not support gather_writes yet in regmap, A bulk write on paged register would be silently ignored after programming page. This is because local variable 'ret' value in regmap_raw_write_impl() gets reset to 0 once page register is written successfully and the code below checks for 'ret' value to be -ENOTSUPP before linearising the write buffer to send to bus->write(). Fix this by resetting the 'ret' value to -ENOTSUPP in cases where gather_writes() is not supported or single register write is not possible. Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-06-11PM / core: Propagate dev->power.wakeup_path when no callbacksUlf Hansson1-0/+4
[ Upstream commit dc351d4c5f4fe4d0f274d6d660227be0c3a03317 ] The dev->power.direct_complete flag may become set in device_prepare() in case the device don't have any PM callbacks (dev->power.no_pm_callbacks is set). This leads to a broken behaviour, when there is child having wakeup enabled and relies on its parent to be used in the wakeup path. More precisely, when the direct complete path becomes selected for the child in __device_suspend(), the propagation of the dev->power.wakeup_path becomes skipped as well. Let's address this problem, by checking if the device is a part the wakeup path or has wakeup enabled, then prevent the direct complete path from being used. Reported-by: Loic Pallardy <loic.pallardy@st.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> [ rjw: Comment cleanup ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-16x86/speculation/mds: Add sysfs reporting for MDSThomas Gleixner1-0/+8
commit 8a4b06d391b0a42a373808979b5028f5c84d9c6a upstream. Add the sysfs reporting file for MDS. It exposes the vulnerability and mitigation state similar to the existing files for the other speculative hardware vulnerabilities. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jon Masters <jcm@redhat.com> Tested-by: Jon Masters <jcm@redhat.com> [bwh: Backported to 4.4: - Test x86_hyper instead of using hypervisor_is_type() - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23PM / wakeup: Rework wakeup source timer cancellationViresh Kumar1-1/+7
commit 1fad17fb1bbcd73159c2b992668a6957ecc5af8a upstream. If wakeup_source_add() is called right after wakeup_source_remove() for the same wakeup source, timer_setup() may be called for a potentially scheduled timer which is incorrect. To avoid that, move the wakeup source timer cancellation from wakeup_source_drop() to wakeup_source_remove(). Moreover, make wakeup_source_remove() clear the timer function after canceling the timer to let wakeup_source_not_registered() treat unregistered wakeup sources in the same way as the ones that have never been registered. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: 4.4+ <stable@vger.kernel.org> # 4.4+ [ rjw: Subject, changelog, merged two patches together ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-06drivers: core: Remove glue dirs from sysfs earlierBenjamin Herrenschmidt1-0/+2
commit 726e41097920a73e4c7c33385dcc0debb1281e18 upstream. For devices with a class, we create a "glue" directory between the parent device and the new device with the class name. This directory is never "explicitely" removed when empty however, this is left to the implicit sysfs removal done by kobject_release() when the object loses its last reference via kobject_put(). This is problematic because as long as it's not been removed from sysfs, it is still present in the class kset and in sysfs directory structure. The presence in the class kset exposes a use after free bug fixed by the previous patch, but the presence in sysfs means that until the kobject is released, which can take a while (especially with kobject debugging), any attempt at re-creating such as binding a new device for that class/parent pair, will result in a sysfs duplicate file name error. This fixes it by instead doing an explicit kobject_del() when the glue dir is empty, by keeping track of the number of child devices of the gluedir. This is made easy by the fact that all glue dir operations are done with a global mutex, and there's already a function (cleanup_glue_dir) called in all the right places taking that mutex that can be enhanced for this. It appears that this was in fact the intent of the function, but the implementation was wrong. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Zubin Mithra <zsm@chromium.org> Cc: Guenter Roeck <groeck@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-26sysfs: Disable lockdep for driver bind/unbind filesDaniel Vetter1-2/+5
[ Upstream commit 4f4b374332ec0ae9c738ff8ec9bed5cd97ff9adc ] This is the much more correct fix for my earlier attempt at: https://lkml.org/lkml/2018/12/10/118 Short recap: - There's not actually a locking issue, it's just lockdep being a bit too eager to complain about a possible deadlock. - Contrary to what I claimed the real problem is recursion on kn->count. Greg pointed me at sysfs_break_active_protection(), used by the scsi subsystem to allow a sysfs file to unbind itself. That would be a real deadlock, which isn't what's happening here. Also, breaking the active protection means we'd need to manually handle all the lifetime fun. - With Rafael we discussed the task_work approach, which kinda works, but has two downsides: It's a functional change for a lockdep annotation issue, and it won't work for the bind file (which needs to get the errno from the driver load function back to userspace). - Greg also asked why this never showed up: To hit this you need to unregister a 2nd driver from the unload code of your first driver. I guess only gpus do that. The bug has always been there, but only with a recent patch series did we add more locks so that lockdep built a chain from unbinding the snd-hda driver to the acpi_video_unregister call. Full lockdep splat: [12301.898799] ============================================ [12301.898805] WARNING: possible recursive locking detected [12301.898811] 4.20.0-rc7+ #84 Not tainted [12301.898815] -------------------------------------------- [12301.898821] bash/5297 is trying to acquire lock: [12301.898826] 00000000f61c6093 (kn->count#39){++++}, at: kernfs_remove_by_name_ns+0x3b/0x80 [12301.898841] but task is already holding lock: [12301.898847] 000000005f634021 (kn->count#39){++++}, at: kernfs_fop_write+0xdc/0x190 [12301.898856] other info that might help us debug this: [12301.898862] Possible unsafe locking scenario: [12301.898867] CPU0 [12301.898870] ---- [12301.898874] lock(kn->count#39); [12301.898879] lock(kn->count#39); [12301.898883] *** DEADLOCK *** [12301.898891] May be due to missing lock nesting notation [12301.898899] 5 locks held by bash/5297: [12301.898903] #0: 00000000cd800e54 (sb_writers#4){.+.+}, at: vfs_write+0x17f/0x1b0 [12301.898915] #1: 000000000465e7c2 (&of->mutex){+.+.}, at: kernfs_fop_write+0xd3/0x190 [12301.898925] #2: 000000005f634021 (kn->count#39){++++}, at: kernfs_fop_write+0xdc/0x190 [12301.898936] #3: 00000000414ef7ac (&dev->mutex){....}, at: device_release_driver_internal+0x34/0x240 [12301.898950] #4: 000000003218fbdf (register_count_mutex){+.+.}, at: acpi_video_unregister+0xe/0x40 [12301.898960] stack backtrace: [12301.898968] CPU: 1 PID: 5297 Comm: bash Not tainted 4.20.0-rc7+ #84 [12301.898974] Hardware name: Hewlett-Packard HP EliteBook 8460p/161C, BIOS 68SCF Ver. F.01 03/11/2011 [12301.898982] Call Trace: [12301.898989] dump_stack+0x67/0x9b [12301.898997] __lock_acquire+0x6ad/0x1410 [12301.899003] ? kernfs_remove_by_name_ns+0x3b/0x80 [12301.899010] ? find_held_lock+0x2d/0x90 [12301.899017] ? mutex_spin_on_owner+0xe4/0x150 [12301.899023] ? find_held_lock+0x2d/0x90 [12301.899030] ? lock_acquire+0x90/0x180 [12301.899036] lock_acquire+0x90/0x180 [12301.899042] ? kernfs_remove_by_name_ns+0x3b/0x80 [12301.899049] __kernfs_remove+0x296/0x310 [12301.899055] ? kernfs_remove_by_name_ns+0x3b/0x80 [12301.899060] ? kernfs_name_hash+0xd/0x80 [12301.899066] ? kernfs_find_ns+0x6c/0x100 [12301.899073] kernfs_remove_by_name_ns+0x3b/0x80 [12301.899080] bus_remove_driver+0x92/0xa0 [12301.899085] acpi_video_unregister+0x24/0x40 [12301.899127] i915_driver_unload+0x42/0x130 [i915] [12301.899160] i915_pci_remove+0x19/0x30 [i915] [12301.899169] pci_device_remove+0x36/0xb0 [12301.899176] device_release_driver_internal+0x185/0x240 [12301.899183] unbind_store+0xaf/0x180 [12301.899189] kernfs_fop_write+0x104/0x190 [12301.899195] __vfs_write+0x31/0x180 [12301.899203] ? rcu_read_lock_sched_held+0x6f/0x80 [12301.899209] ? rcu_sync_lockdep_assert+0x29/0x50 [12301.899216] ? __sb_start_write+0x13c/0x1a0 [12301.899221] ? vfs_write+0x17f/0x1b0 [12301.899227] vfs_write+0xb9/0x1b0 [12301.899233] ksys_write+0x50/0xc0 [12301.899239] do_syscall_64+0x4b/0x180 [12301.899247] entry_SYSCALL_64_after_hwframe+0x49/0xbe [12301.899253] RIP: 0033:0x7f452ac7f7a4 [12301.899259] Code: 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 80 00 00 00 00 8b 05 aa f0 2c 00 48 63 ff 85 c0 75 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 f3 c3 66 90 55 53 48 89 d5 48 89 f3 48 83 [12301.899273] RSP: 002b:00007ffceafa6918 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [12301.899282] RAX: ffffffffffffffda RBX: 000000000000000d RCX: 00007f452ac7f7a4 [12301.899288] RDX: 000000000000000d RSI: 00005612a1abf7c0 RDI: 0000000000000001 [12301.899295] RBP: 00005612a1abf7c0 R08: 000000000000000a R09: 00005612a1c46730 [12301.899301] R10: 000000000000000a R11: 0000000000000246 R12: 000000000000000d [12301.899308] R13: 0000000000000001 R14: 00007f452af4a740 R15: 000000000000000d Looking around I've noticed that usb and i2c already handle similar recursion problems, where a sysfs file can unbind the same type of sysfs somewhere else in the hierarchy. Relevant commits are: commit 356c05d58af05d582e634b54b40050c73609617b Author: Alan Stern <stern@rowland.harvard.edu> Date: Mon May 14 13:30:03 2012 -0400 sysfs: get rid of some lockdep false positives commit e9b526fe704812364bca07edd15eadeba163ebfb Author: Alexander Sverdlin <alexander.sverdlin@nsn.com> Date: Fri May 17 14:56:35 2013 +0200 i2c: suppress lockdep warning on delete_device Implement the same trick for driver bind/unbind. v2: Put the macro into bus.c (Greg). Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Ramalingam C <ramalingam.c@intel.com> Cc: Arend van Spriel <aspriel@gmail.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Bartosz Golaszewski <brgl@bgdev.pl> Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com> Cc: Vivek Gautam <vivek.gautam@codeaurora.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-10-13PM / core: Clear the direct_complete flag on errorsRafael J. Wysocki1-1/+4
commit 69e445ab8b66a9f30519842ef18be555d3ee9b51 upstream. If __device_suspend() runs asynchronously (in which case the device passed to it is in dpm_suspended_list at that point) and it returns early on an error or pending wakeup, and the power.direct_complete flag has been set for the device already, the subsequent device_resume() will be confused by that and it will call pm_runtime_enable() incorrectly, as runtime PM has not been disabled for the device by __device_suspend(). To avoid that, clear power.direct_complete if __device_suspend() is not going to disable runtime PM for the device before returning. Fixes: aae4518b3124 (PM / sleep: Mechanism to avoid resuming runtime-suspended devices unnecessarily) Reported-by: Al Cooper <alcooperx@gmail.com> Tested-by: Al Cooper <alcooperx@gmail.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Cc: 3.16+ <stable@vger.kernel.org> # 3.16+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-08-15x86/speculation/l1tf: Add sysfs reporting for l1tfAndi Kleen1-0/+8
commit 17dbca119312b4e8173d4e25ff64262119fcef38 upstream L1TF core kernel workarounds are cheap and normally always enabled, However they still should be reported in sysfs if the system is vulnerable or mitigated. Add the necessary CPU feature/bug bits. - Extend the existing checks for Meltdowns to determine if the system is vulnerable. All CPUs which are not vulnerable to Meltdown are also not vulnerable to L1TF - Check for 32bit non PAE and emit a warning as there is no practical way for mitigation due to the limited physical address bits - If the system has more than MAX_PA/2 physical memory the invert page workarounds don't protect the system against the L1TF attack anymore, because an inverted physical address will also point to valid memory. Print a warning in this case and report that the system is vulnerable. Add a function which returns the PFN limit for the L1TF mitigation, which will be used in follow up patches for sanity and range checks. [ tglx: Renamed the CPU feature bit to L1TF_PTEINV ] [ dwmw2: Backport to 4.9 (cpufeatures.h, E820) ] Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Dave Hansen <dave.hansen@intel.com> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-28driver core: Partially revert "driver core: correct device's shutdown order"Rafael J. Wysocki1-8/+0
commit 722e5f2b1eec7de61117b7c0a7914761e3da2eda upstream. Commit 52cdbdd49853 (driver core: correct device's shutdown order) introduced a regression by breaking device shutdown on some systems. Namely, the devices_kset_move_last() call in really_probe() added by that commit is a mistake as it may cause parents to follow children in the devices_kset list which then causes shutdown to fail. For example, if a device has children before really_probe() is called for it (which is not uncommon), that call will cause it to be reordered after the children in the devices_kset list and the ordering of that list will not reflect the correct device shutdown order any more. Also it causes the devices_kset list to be constantly reordered until all drivers have been probed which is totally pointless overhead in the majority of cases and it only covered an issue with system shutdown, while system-wide suspend/resume potentially had the same issue on the affected platforms (which was not covered). Moreover, the shutdown issue originally addressed by the change in really_probe() made by commit 52cdbdd49853 is not present in 4.18-rc any more, since dra7 started to use the sdhci-omap driver which doesn't disable any regulators during shutdown, so the really_probe() part of commit 52cdbdd49853 can be safely reverted. [The original issue was related to the omap_hsmmc driver used by dra7 previously.] For the above reasons, revert the really_probe() modifications made by commit 52cdbdd49853. The other code changes made by commit 52cdbdd49853 are useful and they need not be reverted. Fixes: 52cdbdd49853 (driver core: correct device's shutdown order) Link: https://lore.kernel.org/lkml/CAFgQCTt7VfqM=UyCnvNFxrSw8Z6cUtAi3HUwR4_xPAc03SgHjQ@mail.gmail.com/ Reported-by: Pingfan Liu <kernelfans@gmail.com> Tested-by: Pingfan Liu <kernelfans@gmail.com> Reviewed-by: Kishon Vijay Abraham I <kishon@ti.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-25x86/bugs: Expose /sys/../spec_store_bypassKonrad Rzeszutek Wilk1-0/+8
commit c456442cd3a59eeb1d60293c26cbe2ff2c4e42cf upstream Add the sysfs file for the new vulerability. It does not do much except show the words 'Vulnerable' for recent x86 cores. Intel cores prior to family 6 are known not to be vulnerable, and so are some Atoms and some Xeon Phi. It assumes that older Cyrix, Centaur, etc. cores are immune. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Srivatsa S. Bhat <srivatsa@csail.mit.edu> Reviewed-by: Matt Helsley (VMware) <matt.helsley@gmail.com> Reviewed-by: Alexey Makhalov <amakhalov@vmware.com> Reviewed-by: Bo Gan <ganb@vmware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-03driver core: Don't ignore class_dir_create_and_add() failure.Tetsuo Handa1-2/+12
commit 84d0c27d6233a9ba0578b20f5a09701eb66cee42 upstream. syzbot is hitting WARN() at kernfs_add_one() [1]. This is because kernfs_create_link() is confused by previous device_add() call which continued without setting dev->kobj.parent field when get_device_parent() failed by memory allocation fault injection. Fix this by propagating the error from class_dir_create_and_add() to the calllers of get_device_parent(). [1] https://syzkaller.appspot.com/bug?id=fae0fb607989ea744526d1c082a5b8de6529116f Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reported-by: syzbot <syzbot+df47f81c226b31d89fb1@syzkaller.appspotmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-24regmap: Fix reversed bounds check in regmap_raw_write()Dan Carpenter1-1/+1
commit f00e71091ab92eba52122332586c6ecaa9cd1a56 upstream. We're supposed to be checking that "val_len" is not too large but instead we check if it is smaller than the max. The only function affected would be regmap_i2c_smbus_i2c_write() in drivers/base/regmap/regmap-i2c.c. Strangely that function has its own limit check which returns an error if (count >= I2C_SMBUS_BLOCK_MAX) so it doesn't look like it has ever been able to do anything except return an error. Fixes: c335931ed9d2 ("regmap: Add raw_write/read checks for max_raw_write/read sizes") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-31drivers: base: cacheinfo: fix boot error message when acpi is enabledSudeep Holla1-4/+8
commit 55877ef45fbd7f975d078426866b7d1a2435dcc3 upstream. ARM64 enables both CONFIG_OF and CONFIG_ACPI and the firmware can pass both ACPI tables and the device tree. Based on the kernel parameter, one of the two will be chosen. If acpi is enabled, then device tree is not unflattened. Currently ARM64 platforms report: " Failed to find cpu0 device node Unable to detect cache hierarchy from DT for CPU 0 " which is incorrect when booting with ACPI. Also latest ACPI v6.1 has no support for cache properties/hierarchy. This patch adds check for unflattened device tree and also returns as "not supported" if ACPI is runtime enabled. It also removes the reference to DT from the error message as the cache hierarchy can be detected from the firmware(OF/DT/ACPI) Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-31drivers: base: cacheinfo: fix x86 with CONFIG_OF enabledSudeep Holla1-0/+3
commit fac51482577d5e05bbb0efa8d602a3c2111098bf upstream. With CONFIG_OF enabled on x86, we get the following error on boot: " Failed to find cpu0 device node Unable to detect cache hierarchy from DT for CPU 0 " and the cacheinfo fails to get populated in the corresponding sysfs entries. This is because cache_setup_of_node looks for of_node for setting up the shared cpu_map without checking that it's already populated in the architecture specific callback. In order to indicate that the shared cpu_map is already populated, this patch introduces a boolean `cpu_map_populated` in struct cpu_cacheinfo that can be used by the generic code to skip cache_shared_cpu_map_setup. This patch also sets that boolean for x86. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-31PM / sleep: declare __tracedata symbols as char[] rather than charEric Biggers1-2/+2
commit f97238373b8662a6d580e204df2e7bcbfa43e27a upstream. Accessing more than one byte from a symbol declared simply 'char' is undefined behavior, as reported by UBSAN: UBSAN: Undefined behaviour in drivers/base/power/trace.c:178:18 load of address ffffffff8203fc78 with insufficient space for an object of type 'char' Avoid this by declaring the symbols as arrays. Signed-off-by: Eric Biggers <ebiggers3@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-17sysfs/cpu: Add vulnerability folderThomas Gleixner2-0/+51
commit 87590ce6e373d1a5401f6539f0c59ef92dd924a9 upstream. As the meltdown/spectre problem affects several CPU architectures, it makes sense to have common way to express whether a system is affected by a particular vulnerability or not. If affected the way to express the mitigation should be common as well. Create /sys/devices/system/cpu/vulnerabilities folder and files for meltdown, spectre_v1 and spectre_v2. Allow architectures to override the show function. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linuxfoundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: David Woodhouse <dwmw@amazon.co.uk> Link: https://lkml.kernel.org/r/20180107214913.096657732@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-16isa: Prevent NULL dereference in isa_bus driver callbacksWilliam Breathitt Gray1-5/+5
commit 5a244727f428a06634f22bb890e78024ab0c89f3 upstream. The isa_driver structure for an isa_bus device is stored in the device platform_data member of the respective device structure. This platform_data member may be reset to NULL if isa_driver match callback for the device fails, indicating a device unsupported by the ISA driver. This patch fixes a possible NULL pointer dereference if one of the isa_driver callbacks to attempted for an unsupported device. This error should not occur in practice since ISA devices are typically manually configured and loaded by the users, but we may as well prevent this error from popping up for the 0day testers. Fixes: a5117ba7da37 ("[PATCH] Driver model: add ISA bus") Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-30PM / OPP: Add missing of_node_put(np)Tobias Jordan1-0/+1
commit 7978db344719dab1e56d05e6fc04aaaddcde0a5e upstream. The for_each_available_child_of_node() loop in _of_add_opp_table_v2() doesn't drop the reference to "np" on errors. Fix that. Fixes: 274659029c9d (PM / OPP: Add support to parse "operating-points-v2" bindings) Signed-off-by: Tobias Jordan <Tobias.Jordan@elektrobit.com> [ VK: Improved commit log. ] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-08PM / wakeirq: report a wakeup_event on dedicated wekup irqGrygorii Strashko1-0/+7
[ Upstream commit 09bb6e93956ae5175b96905b723ec879c3ca0765 ] There are two reasons for reporting wakeup event when dedicated wakeup IRQ is triggered: - wakeup events accounting, so proper statistical data will be displayed in sysfs and debugfs; - there are small window when System is entering suspend during which dedicated wakeup IRQ can be lost: dpm_suspend_noirq() |- device_wakeup_arm_wake_irqs() |- dev_pm_arm_wake_irq(X) |- IRQ is enabled and marked as wakeup source [1]... |- suspend_device_irqs() |- suspend_device_irq(X) |- irqd_set(X, IRQD_WAKEUP_ARMED); |- wakup IRQ armed The wakeup IRQ can be lost if it's triggered at point [1] and not armed yet. Hence, fix above cases by adding simple pm_wakeup_event() call in handle_threaded_wake_irq(). Fixes: 4990d4fe327b (PM / Wakeirq: Add automated device wake IRQ handling) Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> Tested-by: Keerthy <j-keerthy@ti.com> [ tony@atomide.com: added missing return to avoid warnings ] Tested-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-12driver core: platform: Don't read past the end of "driver_override" bufferNicolai Stange1-1/+2
commit bf563b01c2895a4bfd1a29cc5abc67fe706ecffd upstream. When printing the driver_override parameter when it is 4095 and 4094 bytes long, the printing code would access invalid memory because we need count+1 bytes for printing. Reject driver_override values of these lengths in driver_override_store(). This is in close analogy to commit 4efe874aace5 ("PCI: Don't read past the end of sysfs "driver_override" buffer") from Sasha Levin. Fixes: 3d713e0e382e ("driver core: platform: add device binding path 'driver_override'") Signed-off-by: Nicolai Stange <nstange@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-14driver core: bus: Fix a potential double freeChristophe JAILLET1-1/+1
commit 0f9b011d3321ca1079c7a46c18cb1956fbdb7bcb upstream. The .release function of driver_ktype is 'driver_release()'. This function frees the container_of this kobject. So, this memory must not be freed explicitly in the error handling path of 'bus_add_driver()'. Otherwise a double free will occur. Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-07PM / Domains: defer dev_pm_domain_set() until genpd->attach_dev succeeds if ↵Sudeep Holla1-2/+4
present commit 975e83cfb8dc16e7a2fdc58188c77c0c605876c2 upstream. If the genpd->attach_dev or genpd->power_on fails, genpd_dev_pm_attach may return -EPROBE_DEFER initially. However genpd_alloc_dev_data sets the PM domain for the device unconditionally. When subsequent attempts are made to call genpd_dev_pm_attach, it may return -EEXISTS checking dev->pm_domain without re-attempting to call attach_dev or power_on. platform_drv_probe then attempts to call drv->probe as the return value -EEXIST != -EPROBE_DEFER, which may end up in a situation where the device is accessed without it's power domain switched on. Fixes: f104e1e5ef57 (PM / Domains: Re-order initialization of generic_pm_domain_data) Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-28PM / Domains: Fix unsafe iteration over modified list of domain providersKrzysztof Kozlowski1-2/+2
commit b556b15dc04e9b9b98790f04c21acf5e24f994b2 upstream. of_genpd_del_provider() iterates over list of domain provides and removes matching element thus it has to use safe version of list iteration. Fixes: aa42240ab254 (PM / Domains: Add generic OF-based PM domain look-up) Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-28PM / Domains: Fix unsafe iteration over modified list of device linksKrzysztof Kozlowski1-2/+2
commit c6e83cac3eda5f7dd32ee1453df2f7abb5c6cd46 upstream. pm_genpd_remove_subdomain() iterates over domain's master_links list and removes matching element thus it has to use safe version of list iteration. Fixes: f721889ff65a ("PM / Domains: Support for generic I/O PM domains (v8)") Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21PM / QoS: return -EINVAL for bogus stringsDan Carpenter1-0/+2
commit 2ca30331c156ca9e97643ad05dd8930b8fe78b01 upstream. In the current code, if the user accidentally writes a bogus command to this sysfs file, then we set the latency tolerance to an uninitialized variable. Fixes: 2d984ad132a8 (PM / QoS: Introcuce latency tolerance device PM QoS type) Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21PM / wakeirq: Convert to SRCUThomas Gleixner1-12/+18
commit ea0212f40c6bc0594c8eff79266759e3ecd4bacc upstream. The wakeirq infrastructure uses RCU to protect the list of wakeirqs. That breaks the irq bus locking infrastructure, which is allows sleeping functions to be called so interrupt controllers behind slow busses, e.g. i2c, can be handled. The wakeirq functions hold rcu_read_lock and call into irq functions, which in case of interrupts using the irq bus locking will trigger a might_sleep() splat. Convert the wakeirq infrastructure to Sleepable RCU and unbreak it. Fixes: 4990d4fe327b (PM / Wakeirq: Add automated device wake IRQ handling) Reported-by: Brian Norris <briannorris@chromium.org> Suggested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tested-by: Tony Lindgren <tony@atomide.com> Tested-by: Brian Norris <briannorris@chromium.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21Add "shutdown" to "struct class".Josh Zimmerman1-1/+5
commit f77af15165847406b15d8f70c382c4cb15846b2a upstream. The TPM class has some common shutdown code that must be executed for all drivers. This adds some needed functionality for that. Signed-off-by: Josh Zimmerman <joshz@google.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Fixes: 74d6b3ceaa17 ("tpm: fix suspend/resume paths for TPM 2.0") Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: James Morris <james.l.morris@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-15driver core: platform: fix race condition with driver_overrideAdrian Salido1-2/+9
commit 6265539776a0810b7ce6398c27866ddb9c6bd154 upstream. The driver_override implementation is susceptible to race condition when different threads are reading vs storing a different driver override. Add locking to avoid race condition. Fixes: 3d713e0e382e ("driver core: platform: add device binding path 'driver_override'") Cc: stable@vger.kernel.org Signed-off-by: Adrian Salido <salidoa@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-17PM / runtime: Avoid false-positive warnings from might_sleep_if()Rafael J. Wysocki1-5/+6
[ Upstream commit a9306a63631493afc75893a4ac405d4e1cbae6aa ] The might_sleep_if() assertions in __pm_runtime_idle(), __pm_runtime_suspend() and __pm_runtime_resume() may generate false-positive warnings in some situations. For example, that happens if a nested pm_runtime_get_sync()/pm_runtime_put() pair is executed with disabled interrupts within an outer pm_runtime_get_sync()/pm_runtime_put() section for the same device. [Generally, pm_runtime_get_sync() may sleep, so it should not be called with disabled interrupts, but in this particular case the previous pm_runtime_get_sync() guarantees that the device will not be suspended, so the inner pm_runtime_get_sync() will return immediately after incrementing the device's usage counter.] That started to happen in the i915 driver in 4.10-rc, leading to the following splat: BUG: sleeping function called from invalid context at drivers/base/power/runtime.c:1032 in_atomic(): 1, irqs_disabled(): 0, pid: 1500, name: Xorg 1 lock held by Xorg/1500: #0: (&dev->struct_mutex){+.+.+.}, at: [<ffffffffa0680c13>] i915_mutex_lock_interruptible+0x43/0x140 [i915] CPU: 0 PID: 1500 Comm: Xorg Not tainted Call Trace: dump_stack+0x85/0xc2 ___might_sleep+0x196/0x260 __might_sleep+0x53/0xb0 __pm_runtime_resume+0x7a/0x90 intel_runtime_pm_get+0x25/0x90 [i915] aliasing_gtt_bind_vma+0xaa/0xf0 [i915] i915_vma_bind+0xaf/0x1e0 [i915] i915_gem_execbuffer_relocate_entry+0x513/0x6f0 [i915] i915_gem_execbuffer_relocate_vma.isra.34+0x188/0x250 [i915] ? trace_hardirqs_on+0xd/0x10 ? i915_gem_execbuffer_reserve_vma.isra.31+0x152/0x1f0 [i915] ? i915_gem_execbuffer_reserve.isra.32+0x372/0x3a0 [i915] i915_gem_do_execbuffer.isra.38+0xa70/0x1a40 [i915] ? __might_fault+0x4e/0xb0 i915_gem_execbuffer2+0xc5/0x260 [i915] ? __might_fault+0x4e/0xb0 drm_ioctl+0x206/0x450 [drm] ? i915_gem_execbuffer+0x340/0x340 [i915] ? __fget+0x5/0x200 do_vfs_ioctl+0x91/0x6f0 ? __fget+0x111/0x200 ? __fget+0x5/0x200 SyS_ioctl+0x79/0x90 entry_SYSCALL_64_fastpath+0x23/0xc6 even though the code triggering it is correct. Unfortunately, the might_sleep_if() assertions in question are too coarse-grained to cover such cases correctly, so make them a bit less sensitive in order to avoid the false-positives. Reported-and-tested-by: Sedat Dilek <sedat.dilek@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-09base/memory, hotplug: fix a kernel oops in show_valid_zones()Toshi Kani1-6/+5
commit a96dfddbcc04336bbed50dc2b24823e45e09e80c upstream. Reading a sysfs "memoryN/valid_zones" file leads to the following oops when the first page of a range is not backed by struct page. show_valid_zones() assumes that 'start_pfn' is always valid for page_zone(). BUG: unable to handle kernel paging request at ffffea017a000000 IP: show_valid_zones+0x6f/0x160 This issue may happen on x86-64 systems with 64GiB or more memory since their memory block size is bumped up to 2GiB. [1] An example of such systems is desribed below. 0x3240000000 is only aligned by 1GiB and this memory block starts from 0x3200000000, which is not backed by struct page. BIOS-e820: [mem 0x0000003240000000-0x000000603fffffff] usable Since test_pages_in_a_zone() already checks holes, fix this issue by extending this function to return 'valid_start' and 'valid_end' for a given range. show_valid_zones() then proceeds with the valid range. [1] 'Commit bdee237c0343 ("x86: mm: Use 2GB memory block size on large-memory x86-64 systems")' Link: http://lkml.kernel.org/r/20170127222149.30893-3-toshi.kani@hpe.com Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Zhang Zhen <zhenzhang.zhang@huawei.com> Cc: Reza Arbab <arbab@linux.vnet.ibm.com> Cc: David Rientjes <rientjes@google.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: <stable@vger.kernel.org> [4.4+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12PM / wakeirq: Fix dedicated wakeirq for drivers not using autosuspendTony Lindgren3-15/+88
commit bed570307ed78f21b77cb04a1df781dee4a8f05a upstream. I noticed some wakeirq flakeyness with consumer drivers not using autosuspend. For drivers not using autosuspend, the wakeirq may never get unmasked in rpm_suspend() because of irq desc->depth. We are configuring dedicated wakeirqs to start with IRQ_NOAUTOEN as we naturally don't want them running until rpm_suspend() is called. However, when a consumer driver initially calls pm_runtime_get(), we now wrongly start with disable_irq_nosync() call on the dedicated wakeirq that is disabled to start with. This causes desc->depth to toggle between 1 and 2 instead of the usual 0 and 1. This can prevent enable_irq() from unmasking the wakeirq as that only happens at desc->depth 1. This does not necessarily show up with drivers using autosuspend as there is time for disable_irq_nosync() before rpm_suspend() gets called after the autosuspend timeout. Let's fix the issue by adding wirq->status that lazily gets set on the first rpm_suspend(). We also need PM runtime core private functions for dev_pm_enable_wake_irq_check() and dev_pm_disable_wake_irq_check() so we can enable the dedicated wakeirq on the first rpm_suspend(). While at it, let's also fix the comments for dev_pm_enable_wake_irq() and dev_pm_disable_wake_irq(). Those can still be used by the consumer drivers as needed because the IRQ core manages the interrupt usecount for us. Fixes: 4990d4fe327b (PM / Wakeirq: Add automated device wake IRQ handling) Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-09firmware: fix usermode helper fallback loadingYves-Alexis Perez1-3/+4
commit 2e700f8d85975f516ccaad821278c1fe66b2cc98 upstream. When you use the firmware usermode helper fallback with a timeout value set to a value greater than INT_MAX (2147483647) a cast overflow issue causes the timeout value to go negative and breaks all usermode helper loading. This regression was introduced through commit 68ff2a00dbf5 ("firmware_loader: handle timeout via wait_for_completion_interruptible_timeout()") on kernel v4.0. The firmware_class drivers relies on the firmware usermode helper fallback as a mechanism to look for firmware if the direct filesystem search failed only if: a) You've enabled CONFIG_FW_LOADER_USER_HELPER_FALLBACK (not many distros): Then all of these callers will rely on the fallback mechanism in case the firmware is not found through an initial direct filesystem lookup: o request_firmware() o request_firmware_into_buf() o request_firmware_nowait() b) If you've only enabled CONFIG_FW_LOADER_USER_HELPER (most distros): Then only callers using request_firmware_nowait() with the second argument set to false, this explicitly is requesting the UMH firmware fallback to be relied on in case the first filesystem lookup fails. Using Coccinelle SmPL grammar we have identified only two drivers explicitly requesting the UMH firmware fallback mechanism: - drivers/firmware/dell_rbu.c - drivers/leds/leds-lp55xx-common.c Since most distributions only enable CONFIG_FW_LOADER_USER_HELPER the biggest impact of this regression are users of the dell_rbu and leds-lp55xx-common device driver which required the UMH to find their respective needed firmwares. The default timeout for the UMH is set to 60 seconds always, as of commit 68ff2a00dbf5 ("firmware_loader: handle timeout via wait_for_completion_interruptible_timeout()") the timeout was bumped to MAX_JIFFY_OFFSET ((LONG_MAX >> 1)-1). Additionally the MAX_JIFFY_OFFSET value was also used if the timeout was configured by a user to 0. The following works: echo 2147483647 > /sys/class/firmware/timeout But both of the following set the timeout to MAX_JIFFY_OFFSET even if we display 0 back to userspace: echo 2147483648 > /sys/class/firmware/timeout cat /sys/class/firmware/timeout 0 echo 0> /sys/class/firmware/timeout cat /sys/class/firmware/timeout 0 A max value of INT_MAX (2147483647) seconds is therefore implicit due to the another cast with simple_strtol(). This fixes the secondary cast (the first one is simple_strtol() but its an issue only by forcing an implicit limit) by re-using the timeout variable and only setting retval in appropriate cases. Lastly worth noting systemd had ripped out the UMH firmware fallback mechanism from udev since udev 2014 via commit be2ea723b1d023b3d ("udev: remove userspace firmware loading support"), so as of systemd v217. Signed-off-by: Yves-Alexis Perez <corsac@corsac.net> Fixes: 68ff2a00dbf5 "firmware_loader: handle timeout via wait_for_completion_interruptible_timeout()" Cc: Luis R. Rodriguez <mcgrof@kernel.org> Cc: Ming Lei <ming.lei@canonical.com> Cc: Bjorn Andersson <bjorn.andersson@linaro.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Luis R. Rodriguez <mcgrof@kernel.org> Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> [mcgrof@kernel.org: gave commit log a whole lot of love] Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-06driver core: fix race between creating/querying glue dir and its cleanupMing Lei1-10/+29
commit cebf8fd16900fdfd58c0028617944f808f97fe50 upstream. The global mutex of 'gdp_mutex' is used to serialize creating/querying glue dir and its cleanup. Turns out it isn't a perfect way because part(kobj_kset_leave()) of the actual cleanup action() is done inside the release handler of the glue dir kobject. That means gdp_mutex has to be held before releasing the last reference count of the glue dir kobject. This patch moves glue dir's cleanup after kobject_del() in device_del() for avoiding the race. Cc: Yijing Wang <wangyijing@huawei.com> Reported-by: Chandra Sekhar Lingutla <clingutla@codeaurora.org> Signed-off-by: Ming Lei <ming.lei@canonical.com> Cc: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-26PM / sleep: don't suspend parent when async child suspend_{noirq, late} failsBrian Norris1-4/+4
commit 6f75c3fd56daf547d684127a7f83c283c3c160d1 upstream. Consider two devices, A and B, where B is a child of A, and B utilizes asynchronous suspend (it does not matter whether A is sync or async). If B fails to suspend_noirq() or suspend_late(), or is interrupted by a wakeup (pm_wakeup_pending()), then it aborts and sets the async_error variable. However, device A does not (immediately) check the async_error variable; it may continue to run its own suspend_noirq()/suspend_late() callback. This is bad. We can resolve this problem by doing our error and wakeup checking (particularly, for the async_error flag) after waiting for children to suspend, instead of before. This also helps align the logic for the noirq and late suspend cases with the logic in __device_suspend(). It's easy to observe this erroneous behavior by, for example, forcing a device to sleep a bit in its suspend_noirq() (to ensure the parent is waiting for the child to complete), then return an error, and watch the parent suspend_noirq() still get called. (Or similarly, fake a wakeup event at the right (or is it wrong?) time.) Fixes: de377b397272 (PM / sleep: Asynchronous threads for suspend_late) Fixes: 28b6fd6e3779 (PM / sleep: Asynchronous threads for suspend_noirq) Reported-by: Jeffy Chen <jeffy.chen@rock-chips.com> Signed-off-by: Brian Norris <briannorris@chromium.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-28platform: don't return 0 from platform_get_irq[_byname]() on errorSergei Shtylyov1-2/+2
commit e330b9a6bb35dc7097a4f02cb1ae7b6f96df92af upstream. of_irq_get[_byname]() return 0 iff irq_create_of_mapping() call fails. Returning both error code and 0 on failure is a sign of a misdesigned API, it makes the failure check unnecessarily complex and error prone. We should rely on the platform IRQ resource in this case, not return 0, especially as 0 can be a valid IRQ resource too... Fixes: aff008ad813c ("platform_get_irq: Revert to platform_get_resource if of_irq_get fails") Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-22drivers: base: dma-mapping: page align the size when unmap_kernel_rangePeng Fan1-1/+1
commit 85714108e673cdebf1b96abfd50fb02a29e37577 upstream. When dma_common_free_remap, the input parameter 'size' may not be page aligned. And, met kernel warning when doing iommu dma for usb on i.MX8 platform: " WARNING: CPU: 0 PID: 869 at mm/vmalloc.c:70 vunmap_page_range+0x1cc/0x1d0() Modules linked in: CPU: 0 PID: 869 Comm: kworker/u8:2 Not tainted 4.1.12-00444-gc5f9d1d-dirty #147 Hardware name: Freescale i.MX8DV Sabreauto (DT) Workqueue: ci_otg ci_otg_work Call trace: [<ffffffc000089920>] dump_backtrace+0x0/0x124 [<ffffffc000089a54>] show_stack+0x10/0x1c [<ffffffc0006d1e6c>] dump_stack+0x84/0xc8 [<ffffffc0000b4568>] warn_slowpath_common+0x98/0xd0 [<ffffffc0000b4664>] warn_slowpath_null+0x14/0x20 [<ffffffc000170348>] vunmap_page_range+0x1c8/0x1d0 [<ffffffc000170388>] unmap_kernel_range+0x20/0x88 [<ffffffc000460ad0>] dma_common_free_remap+0x74/0x84 [<ffffffc0000940d8>] __iommu_free_attrs+0x9c/0x178 [<ffffffc0005032bc>] ehci_mem_cleanup+0x140/0x194 [<ffffffc000503548>] ehci_stop+0x8c/0xdc [<ffffffc0004e8258>] usb_remove_hcd+0xf0/0x1cc [<ffffffc000516bc0>] host_stop+0x1c/0x58 [<ffffffc000514240>] ci_otg_work+0xdc/0x120 [<ffffffc0000c9c34>] process_one_work+0x134/0x33c [<ffffffc0000c9f78>] worker_thread+0x13c/0x47c [<ffffffc0000cf43c>] kthread+0xd8/0xf0 " For dma_common_pages_remap: dma_common_pages_remap |->get_vm_area_caller |->__get_vm_area_node |->size = PAGE_ALIGN(size); Round up to page aligned So, in dma_common_free_remap, we also need a page aligned size, pass 'PAGE_ALIGN(size)' to unmap_kernel_range. Signed-off-by: Peng Fan <van.freenix@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-07-27base: make module_create_drivers_dir race-freeJiri Slaby1-3/+5
commit 7e1b1fc4dabd6ec8e28baa0708866e13fa93c9b3 upstream. Modules which register drivers via standard path (driver_register) in parallel can cause a warning: WARNING: CPU: 2 PID: 3492 at ../fs/sysfs/dir.c:31 sysfs_warn_dup+0x62/0x80 sysfs: cannot create duplicate filename '/module/saa7146/drivers' Modules linked in: hexium_gemini(+) mxb(+) ... ... Call Trace: ... [<ffffffff812e63a2>] sysfs_warn_dup+0x62/0x80 [<ffffffff812e6487>] sysfs_create_dir_ns+0x77/0x90 [<ffffffff8140f2c4>] kobject_add_internal+0xb4/0x340 [<ffffffff8140f5b8>] kobject_add+0x68/0xb0 [<ffffffff8140f631>] kobject_create_and_add+0x31/0x70 [<ffffffff8157a703>] module_add_driver+0xc3/0xd0 [<ffffffff8155e5d4>] bus_add_driver+0x154/0x280 [<ffffffff815604c0>] driver_register+0x60/0xe0 [<ffffffff8145bed0>] __pci_register_driver+0x60/0x70 [<ffffffffa0273e14>] saa7146_register_extension+0x64/0x90 [saa7146] [<ffffffffa0033011>] hexium_init_module+0x11/0x1000 [hexium_gemini] ... As can be (mostly) seen, driver_register causes this call sequence: -> bus_add_driver -> module_add_driver -> module_create_drivers_dir The last one creates "drivers" directory in /sys/module/<...>. When this is done in parallel, the directory is attempted to be created twice at the same time. This can be easily reproduced by loading mxb and hexium_gemini in parallel: while :; do modprobe mxb & modprobe hexium_gemini wait rmmod mxb hexium_gemini saa7146_vv saa7146 done saa7146 calls pci_register_driver for both mxb and hexium_gemini, which means /sys/module/saa7146/drivers is to be created for both of them. Fix this by a new mutex in module_create_drivers_dir which makes the test-and-create "drivers" dir atomic. I inverted the condition and removed 'return' to avoid multiple unlocks or a goto. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Fixes: fe480a2675ed (Modules: only add drivers/ direcory if needed) Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-08PM / sleep: Handle failures in device_suspend_late() consistentlyRafael J. Wysocki1-2/+3
commit 3a17fb329da68cb00558721aff876a80bba2fdb9 upstream. Grygorii Strashko reports: The PM runtime will be left disabled for the device if its .suspend_late() callback fails and async suspend is not allowed for this device. In this case device will not be added in dpm_late_early_list and dpm_resume_early() will ignore this device, as result PM runtime will be disabled for it forever (side effect: after 8 subsequent failures for the same device the PM runtime will be reenabled due to disable_depth overflow). To fix this problem, add devices to dpm_late_early_list regardless of whether or not device_suspend_late() returns errors for them. That will ensure failures in there to be handled consistently for all devices regardless of their async suspend/resume status. Reported-by: Grygorii Strashko <grygorii.strashko@ti.com> Tested-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-08PM / Runtime: Fix error path in pm_runtime_force_resume()Ulf Hansson1-2/+7
commit 0ae3aeefabbeef26294e7a349b51f1c761d46c9f upstream. As pm_runtime_set_active() may fail because the device's parent isn't active, we can end up executing the ->runtime_resume() callback for the device when it isn't allowed. Fix this by invoking pm_runtime_set_active() before running the callback and let's also deal with the error code. Fixes: 37f204164dfb (PM: Add pm_runtime_suspend|resume_force functions) Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-19regmap: spmi: Fix regmap_spmi_ext_read in multi-byte caseJack Pham1-1/+1
commit dec8e8f6e6504aa3496c0f7cc10c756bb0e10f44 upstream. Specifically for the case of reads that use the Extended Register Read Long command, a multi-byte read operation is broken up into 8-byte chunks. However the call to spmi_ext_register_readl() is incorrectly passing 'val_size', which if greater than 8 will always fail. The argument should instead be 'len'. Fixes: c9afbb05a9ff ("regmap: spmi: support base and extended register spaces") Signed-off-by: Jack Pham <jackp@codeaurora.org> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-05PM / Domains: Fix removal of a subdomainJon Hunter1-1/+1
commit beda5fc1ff9b527059290a97b672d2ee0eb7b92f upstream. Commit 30e7a65b3fdb (PM / Domains: Ensure subdomain is not in use before removing) added a test to ensure that a subdomain is not a master to another subdomain or if any devices are using the subdomain before removing. This change incorrectly used the "slave_links" list to determine if the subdomain is a master to another subdomain, where it should have been using the "master_links" list instead. The "slave_links" list will never be empty for a subdomain and so a subdomain can never be removed. Fix this by testing if the "master_links" list is empty instead. Fixes: 30e7a65b3fdb (PM / Domains: Ensure subdomain is not in use before removing) Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Reviewed-by: Thierry Reding <treding@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-05PM / OPP: Initialize u_volt_min/max to a valid valueViresh Kumar1-2/+8
commit c88c395f4a6485f23f81e385c79945d68bcd5c5d upstream. We kept u_volt_min/max initialized to 0, when only the target voltage is present in DT, instead of the target/min/max triplet. This didn't go well with the regulator framework, as on few calls the min voltage was set to target and max was set to 0 and so resulted in a kernel crash like below: kernel BUG at ../drivers/regulator/core.c:216! [<c0684af4>] (regulator_check_voltage) from [<c06857ac>] (regulator_set_voltage_unlocked+0x58/0x230) [<c06857ac>] (regulator_set_voltage_unlocked) from [<c06859ac>] (regulator_set_voltage+0x28/0x54) [<c06859ac>] (regulator_set_voltage) from [<c0775b28>] (_set_opp_voltage+0x30/0x98) [<c0775b28>] (_set_opp_voltage) from [<c0776630>] (dev_pm_opp_set_rate+0xf0/0x28c) [<c0776630>] (dev_pm_opp_set_rate) from [<c096f784>] (__cpufreq_driver_target+0x184/0x2b4) [<c096f784>] (__cpufreq_driver_target) from [<c0973760>] (dbs_check_cpu+0x1b0/0x1f4) [<c0973760>] (dbs_check_cpu) from [<c0973f30>] (cpufreq_governor_dbs+0x324/0x5c4) [<c0973f30>] (cpufreq_governor_dbs) from [<c0970958>] (__cpufreq_governor+0xe4/0x1ec) [<c0970958>] (__cpufreq_governor) from [<c09711e0>] (cpufreq_init_policy+0x64/0x8c) [<c09711e0>] (cpufreq_init_policy) from [<c09718cc>] (cpufreq_online+0x2fc/0x708) [<c09718cc>] (cpufreq_online) from [<c0765ff0>] (subsys_interface_register+0x94/0xd8) [<c0765ff0>] (subsys_interface_register) from [<c0970530>] (cpufreq_register_driver+0x14c/0x19c) [<c0970530>] (cpufreq_register_driver) from [<c09746dc>] (dt_cpufreq_probe+0x70/0xec) [<c09746dc>] (dt_cpufreq_probe) from [<c076907c>] (platform_drv_probe+0x4c/0xb0) [<c076907c>] (platform_drv_probe) from [<c07678e0>] (driver_probe_device+0x214/0x2c0) [<c07678e0>] (driver_probe_device) from [<c0767a18>] (__driver_attach+0x8c/0x90) [<c0767a18>] (__driver_attach) from [<c0765c2c>] (bus_for_each_dev+0x68/0x9c) [<c0765c2c>] (bus_for_each_dev) from [<c0766d78>] (bus_add_driver+0x1a0/0x218) [<c0766d78>] (bus_add_driver) from [<c076810c>] (driver_register+0x78/0xf8) [<c076810c>] (driver_register) from [<c0301d74>] (do_one_initcall+0x90/0x1d8) [<c0301d74>] (do_one_initcall) from [<c1100e14>] (kernel_init_freeable+0x15c/0x1fc) [<c1100e14>] (kernel_init_freeable) from [<c0b27a0c>] (kernel_init+0x8/0xf0) [<c0b27a0c>] (kernel_init) from [<c0307d78>] (ret_from_fork+0x14/0x3c) Code: e1550004 baffffeb e3a00000 e8bd8070 (e7f001f2) Fix that by initializing u_volt_min/max to the target voltage in such cases. Reported-and-tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Fixes: 274659029c9d (PM / OPP: Add support to parse "operating-points-v2" bindings) Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-17base/platform: Fix platform drivers with no probe callbackMartin Wilck1-4/+9
commit 25cad69f21f5532d99e2ee73c8ab6512bcab614c upstream. Since b8b2c7d845d5, platform_drv_probe() is called for all platform devices. If drv->probe is NULL, and dev_pm_domain_attach() fails, platform_drv_probe() will return the error code from dev_pm_domain_attach(). This causes real_probe() to enter the "probe_failed" path and set dev->driver to NULL. Before b8b2c7d845d5, real_probe() would assume success if both dev->bus->probe and drv->probe were missing. As a result, a device and driver could be "bound" together just by matching their names; this doesn't work any more after b8b2c7d845d5. This may cause problems later for certain usage of platform_driver_register() and platform_device_register_simple(). I observed a panic while loading the tpm_tis driver with parameter "force=1" (i.e. registering tpm_tis as a platform driver), because tpm_tis_init's assumption that the device returned by platform_device_register_simple() was bound didn't hold any more (tpmm_chip_alloc() dereferences chip->pdev->driver, causing panic). This patch restores the previous (4.3.0 and earlier) behavior of platform_drv_probe() in the case when the associated platform driver has no "probe" function. Fixes: b8b2c7d845d5 ("base/platform: assert that dev_pm_domain callbacks are called unconditionally") Signed-off-by: Martin Wilck <Martin.Wilck@ts.fujitsu.com> Cc: Martin Fuzzey <mfuzzey@parkeon.com> Acked-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-15Merge branches 'powercap', 'pm-cpufreq' and 'pm-domains'Rafael J. Wysocki1-11/+22
* powercap: powercap / RAPL: fix BIOS lock check * pm-cpufreq: cpufreq: intel_pstate: Minor cleanup for FRAC_BITS cpufreq: tegra: add regulator dependency for T124 * pm-domains: PM / Domains: Allow runtime PM callbacks to be re-used during system PM
2015-12-12drivers/base/memory.c: prohibit offlining of memory blocks with missing sectionsSeth Jennings1-0/+4
Commit bdee237c0343 ("x86: mm: Use 2GB memory block size on large-memory x86-64 systems") and 982792c782ef ("x86, mm: probe memory block size for generic x86 64bit") introduced large block sizes for x86. This made it possible to have multiple sections per memory block where previously, there was a only every one section per block. Since blocks consist of contiguous ranges of section, there can be holes in the blocks where sections are not present. If one attempts to offline such a block, a crash occurs since the code is not designed to deal with this. This patch is a quick fix to gaurd against the crash by not allowing blocks with non-present sections to be offlined. Addresses https://bugzilla.kernel.org/show_bug.cgi?id=107781 Signed-off-by: Seth Jennings <sjennings@variantweb.net> Reported-by: Andrew Banman <abanman@sgi.com> Cc: Daniel J Blueman <daniel@numascale.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Greg KH <greg@kroah.com> Cc: Russ Anderson <rja@sgi.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>