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2015-07-07tick/broadcast: Check for hrtimer broadcast active earlyThomas Gleixner
If the current cpu is the one which has the hrtimer based broadcast queued then we better return busy immediately instead of going through loops and hoops to figure that out. [ Split out from a larger combo patch ] Tested-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Suzuki Poulose <Suzuki.Poulose@arm.com> Cc: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com> Cc: Catalin Marinas <Catalin.Marinas@arm.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1507070929360.3916@nanos
2015-07-07tick/broadcast: Return busy when IPI is pendingThomas Gleixner
Tell the idle code not to go deep if the broadcast IPI is about to arrive. [ Split out from a larger combo patch ] Tested-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Suzuki Poulose <Suzuki.Poulose@arm.com> Cc: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com> Cc: Catalin Marinas <Catalin.Marinas@arm.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1507070929360.3916@nanos
2015-07-07tick/broadcast: Return busy if periodic mode and hrtimer broadcastThomas Gleixner
If the system is in periodic mode and the broadcast device is hrtimer based, return busy as we have no proper handling for this. [ Split out from a larger combo patch ] Tested-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Suzuki Poulose <Suzuki.Poulose@arm.com> Cc: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com> Cc: Catalin Marinas <Catalin.Marinas@arm.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1507070929360.3916@nanos
2015-07-07tick/broadcast: Move the check for periodic mode inside state handlingThomas Gleixner
We need to check more than the periodic mode for proper operation in all runtime combinations. To avoid code duplication move the check into the enter state handling. No functional change. [ Split out from a larger combo patch ] Reported-and-tested-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Suzuki Poulose <Suzuki.Poulose@arm.com> Cc: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com> Cc: Catalin Marinas <Catalin.Marinas@arm.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1507070929360.3916@nanos
2015-07-07tick/broadcast: Prevent deep idle if no broadcast device availableThomas Gleixner
Add a check for a installed broadcast device to the oneshot control function and return busy if not. [ Split out from a larger combo patch ] Reported-and-tested-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Suzuki Poulose <Suzuki.Poulose@arm.com> Cc: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com> Cc: Catalin Marinas <Catalin.Marinas@arm.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1507070929360.3916@nanos
2015-07-07tick/broadcast: Make idle check independent from mode and configThomas Gleixner
Currently the broadcast busy check, which prevents the idle code from going into deep idle, works only in one shot mode. If NOHZ and HIGHRES are off (config or command line) there is no sanity check at all, so under certain conditions cpus are allowed to go into deep idle, where the local timer stops, and are not woken up again because there is no broadcast timer installed or a hrtimer based broadcast device is not evaluated. Move tick_broadcast_oneshot_control() into the common code and provide proper subfunctions for the various config combinations. The common check in tick_broadcast_oneshot_control() is for the C3STOP misfeature flag of the local clock event device. If its not set, idle can proceed. If set, further checks are necessary. Provide checks for the trivial cases: - If broadcast is disabled in the config, then return busy - If oneshot mode (NOHZ/HIGHES) is disabled in the config, return busy if the broadcast device is hrtimer based. - If oneshot mode is enabled in the config call the original tick_broadcast_oneshot_control() function. That function needs extra checks which will be implemented in seperate patches. [ Split out from a larger combo patch ] Reported-and-tested-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Suzuki Poulose <Suzuki.Poulose@arm.com> Cc: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com> Cc: Catalin Marinas <Catalin.Marinas@arm.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1507070929360.3916@nanos
2015-07-07tick/broadcast: Sanity check the shutdown of the local clock_eventThomas Gleixner
The broadcast code shuts down the local clock event unconditionally even if no broadcast device is installed or if the broadcast device is hrtimer based. Add proper sanity checks. [ Split out from a larger combo patch ] Reported-and-tested-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Suzuki Poulose <Suzuki.Poulose@arm.com> Cc: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com> Cc: Catalin Marinas <Catalin.Marinas@arm.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1507070929360.3916@nanos
2015-07-07tick/broadcast: Prevent hrtimer recursionThomas Gleixner
The hrtimer based broadcast vehicle can cause a hrtimer recursion which went unnoticed until we changed the hrtimer expiry code to keep track of the currently running timer. local_timer_interrupt() local_handler() hrtimer_interrupt() expire_hrtimers() broadcast_hrtimer() send_ipis() local_handler() hrtimer_interrupt() .... Solution is simple: Prevent the local handler call from the broadcast code when the broadcast 'device' is hrtimer based. [ Split out from a larger combo patch ] Tested-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Suzuki Poulose <Suzuki.Poulose@arm.com> Cc: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com> Cc: Catalin Marinas <Catalin.Marinas@arm.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1507070929360.3916@nanos
2015-07-07arm64: Keep the ARM64 Kconfig selects sortedCatalin Marinas
Move EDAC_SUPPORT to the right place. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-07-07perf tools: Fix lockup using 32-bit compat vdsoAdrian Hunter
The __machine__findnew_compat() function is called only from __machine__findnew_vdso_compat() which is called only from machine__findnew_vdso() which already holds machine->dsos.lock, so remove locking from __machine__findnew_compat(). This manifests itself tracing 32-bit programs with a 64-bit perf. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Link: http://lkml.kernel.org/r/1436267618-20521-1-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-07-07ARM: socfpga: dts: Fix entries orderWalter Lozano
This patch reorders the nodes alphabetically Signed-off-by: Walter Lozano <walter@vanguardiasur.com.ar> Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>
2015-07-07ACPI / ARM64 : use the new BAD_MADT_GICC_ENTRY macroAl Stone
For those parts of the arm64 ACPI code that need to check GICC subtables in the MADT, use the new BAD_MADT_GICC_ENTRY macro instead of the previous BAD_MADT_ENTRY. The new macro takes into account differences in the size of the GICC subtable that the old macro did not; this caused failures even though the subtable entries are valid. Fixes: aeb823bbacc2 ("ACPICA: ACPI 6.0: Add changes for FADT table.") Signed-off-by: Al Stone <al.stone@linaro.org> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: "Rafael J. Wysocki" <rjw@rjwysocki.net> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-07-07ACPI / ARM64: add BAD_MADT_GICC_ENTRY() macroAl Stone
The BAD_MADT_ENTRY() macro is designed to work for all of the subtables of the MADT. In the ACPI 5.1 version of the spec, the struct for the GICC subtable (struct acpi_madt_generic_interrupt) is 76 bytes long; in ACPI 6.0, the struct is 80 bytes long. But, there is only one definition in ACPICA for this struct -- and that is the 6.0 version. Hence, when BAD_MADT_ENTRY() compares the struct size to the length in the GICC subtable, it fails if 5.1 structs are in use, and there are systems in the wild that have them. This patch adds the BAD_MADT_GICC_ENTRY() that checks the GICC subtable only, accounting for the difference in specification versions that are possible. The BAD_MADT_ENTRY() will continue to work as is for all other MADT subtables. This code is being added to an arm64 header file since that is currently the only architecture using the GICC subtable of the MADT. As a GIC is specific to ARM, it is also unlikely the subtable will be used elsewhere. Fixes: aeb823bbacc2 ("ACPICA: ACPI 6.0: Add changes for FADT table.") Signed-off-by: Al Stone <al.stone@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: "Rafael J. Wysocki" <rjw@rjwysocki.net> [catalin.marinas@arm.com: extra brackets around macro arguments] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-07-07ARM: socfpga: dts: Fix adxl34x formating and compatible stringWalter Lozano
This patch fixes the formating of DTS bindings for the adxl34x digital accelerometer, and updates the compatible string after the deprecation of "adxl345x" compatible string. Signed-off-by: Walter Lozano <walter@vanguardiasur.com.ar> Acked-by: Steffen Trumtrar <s.trumtrar@pengutronix.de> Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>
2015-07-07block/blk-cgroup.c: free per-blkcg data when freeing the blkcgArianna Avanzini
Currently, per-blkcg data is freed each time a policy is deactivated, that is also upon scheduler switch. However, when switching from a scheduler implementing a policy which requires per-blkcg data to another one, that same policy might be active on other devices, and therefore those same per-blkcg data could be still in use. This commit lets per-blkcg data be freed when the blkcg is freed instead of on policy deactivation. Signed-off-by: Arianna Avanzini <avanzini.arianna@gmail.com> Reported-and-tested-by: Michael Kaminsky <kaminsky@cs.cmu.edu> Fixes: e48453c3 ("block, cgroup: implement policy-specific per-blkcg data") Signed-off-by: Jens Axboe <axboe@fb.com>
2015-07-07block: use FIELD_SIZEOF to calculate size of a fieldManinder Singh
use FIELD_SIZEOF instead of open coding Signed-off-by: Maninder Singh <maninder1.s@samsung.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-07-07bio integrity: do not assume bio_integrity_pool exists if bioset existsMike Snitzer
bio_integrity_alloc() and bio_integrity_free() assume that if a bio was allocated from a bioset that that bioset also had its bio_integrity_pool allocated using bioset_integrity_create(). This is a very bad assumption given that bioset_create() and bioset_integrity_create() are completely disjoint. Not all callers of bioset_create() have been trained to also call bioset_integrity_create() -- and they may not care to be. Fix this by falling back to kmalloc'ing 'struct bio_integrity_payload' rather than force all bioset consumers to (wastefully) preallocate a bio_integrity_pool that they very likely won't actually need (given the niche nature of the current block integrity support). Otherwise, a NULL pointer "Kernel BUG" with a trace like the following will be observed (as seen on s390x using zfcp storage) because dm-io doesn't use bioset_integrity_create() when creating its bioset: [ 791.643338] Call Trace: [ 791.643339] ([<00000003df98b848>] 0x3df98b848) [ 791.643341] [<00000000002c5de8>] bio_integrity_alloc+0x48/0xf8 [ 791.643348] [<00000000002c6486>] bio_integrity_prep+0xae/0x2f0 [ 791.643349] [<0000000000371e38>] blk_queue_bio+0x1c8/0x3d8 [ 791.643355] [<000000000036f8d0>] generic_make_request+0xc0/0x100 [ 791.643357] [<000000000036f9b2>] submit_bio+0xa2/0x198 [ 791.643406] [<000003ff801f9774>] dispatch_io+0x15c/0x3b0 [dm_mod] [ 791.643419] [<000003ff801f9b3e>] dm_io+0x176/0x2f0 [dm_mod] [ 791.643423] [<000003ff8074b28a>] do_reads+0x13a/0x1a8 [dm_mirror] [ 791.643425] [<000003ff8074b43a>] do_mirror+0x142/0x298 [dm_mirror] [ 791.643428] [<0000000000154fca>] process_one_work+0x18a/0x3f8 [ 791.643432] [<000000000015598a>] worker_thread+0x132/0x3b0 [ 791.643435] [<000000000015d49a>] kthread+0xd2/0xd8 [ 791.643438] [<00000000005bc0ca>] kernel_thread_starter+0x6/0xc [ 791.643446] [<00000000005bc0c4>] kernel_thread_starter+0x0/0xc Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe <axboe@fb.com>
2015-07-07regulator: max8973: Fix up control flag option for bias controlLaxman Dewangan
The control flag for the bias control is MAX8973_CONTROL_BIAS_ENABLE rather than MAX8973_BIAS_ENABLE which is macro for the bits in register. Fix this typo. Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-07-07ASoC: fsl-ssi: Fix bitclock calculation for master modeJuergen Borleis
According to the datasheet 'pm', 'psr' and 'div2' should never be all 0. Since commit 541b03ad6cfe ("ASoC: fsl_ssi: Fix the incorrect limitation of the bit clock rate") this can happen, because for some bitclock rates 'pm' = 0 seems to be a valid choice but does not work due to hardware restrictions. This results into a bad hardware behaviour (slow audio for example). Feature tested on a i.MX25. Signed-off-by: Juergen Borleis <jbe@pengutronix.de> Acked-by: Nicolin Chen <nicoleotsuka@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-07-07spi: SPI_ZYNQMP_GQSPI should depend on HAS_DMAGeert Uytterhoeven
If NO_DMA=y: ERROR: "dma_unmap_single" [drivers/spi/spi-zynqmp-gqspi.ko] undefined! ERROR: "dma_mapping_error" [drivers/spi/spi-zynqmp-gqspi.ko] undefined! ERROR: "dma_map_single" [drivers/spi/spi-zynqmp-gqspi.ko] undefined! Add a dependency on HAS_DMA to fix this. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Ranjit Waghmode <ranjitw@xilinx.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-07-07spi: spidev: add compatible value for LTC2488Jiri Prchal
Since spidev is no more allowed to use in DT and is really loudly warned about it I'd like to add this compatible value. (Geert Uytterhoeven wrote: "Add the compatible value for your device to the spidev_dt_ids[] array in drivers/spi/spidev.c.") Signed-off-by: Mark Brown <broonie@kernel.org>
2015-07-07drm: add a check for x/y in drm_mode_setcrtcZhao Junwang
legacy setcrtc ioctl does take a 32 bit value which might indeed overflow the checks of crtc_req->x > INT_MAX and crtc_req->y > INT_MAX aren't needed any more with this v2: -polish the annotation according to Daniel's comment Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Zhao Junwang <zhjwpku@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-07-07drm/rockchip: use drm_gem_mmap helpersDaniel Kurtz
Rather than (incompletely [0]) re-implementing drm_gem_mmap() and drm_gem_mmap_obj() helpers, call them directly from the rockchip mmap routines. Once the core functions return successfully, the rockchip mmap routines can still use dma_mmap_attrs() to simply mmap the entire buffer. [0] Previously, we were performing the mmap() without first taking a reference on the underlying gem buffer. This could leak ptes if the gem object is destroyed while userspace is still holding the mapping. Signed-off-by: Daniel Kurtz <djkurtz@chromium.org> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: stable@vger.kernel.org Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2015-07-07Merge branches 'fixes' and 'ioremap' into for-linusRussell King
2015-07-07virtio/s390: rename drivers/s390/kvm -> drivers/s390/virtioCornelia Huck
This more accurately reflects what these drivers actually do. Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-07-07MAINTAINERS: separate section for s390 virtio driversCornelia Huck
The s390-specific virtio drivers have probably more to do with virtio than with kvm today; let's move them out into a separate section to reflect this and to be able to add relevant mailing lists. CC: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-07-07virtio: define virtio_pci_cfg_cap in header.Michael S. Tsirkin
We already have VIRTIO_PCI_CAP_PCI_CFG, let's define the structure that goes with it. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-07-07virtio: Fix typecast of pointer in vring_init()Thomas Huth
The virtio_ring.h header is used in userspace programs (ie. QEMU), too. Here we can not assume that sizeof(pointer) is the same as sizeof(long), e.g. when compiling for Windows, so the typecast in vring_init() should be done with (uintptr_t) instead of (unsigned long). Signed-off-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-07-07virtio scsi: fix unused variable warningStephen Rothwell
drivers/scsi/virtio_scsi.c: In function 'virtscsi_probe': drivers/scsi/virtio_scsi.c:952:11: warning: unused variable 'host_prot' [-Wunused-variable] int err, host_prot; ^ Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-07-07PM / wakeirq: Avoid setting power.wakeirq too hastilyRafael J. Wysocki
If dev_pm_attach_wake_irq() fails, the device's power.wakeirq field should not be set to point to the struct wake_irq passed to that function, as that object will be freed going forward. For this reason, make dev_pm_attach_wake_irq() first call device_wakeup_attach_irq() and only set the device's power.wakeirq field if that's successful. That requires device_wakeup_attach_irq() to be called under the device's power.lock lock, but since dev_pm_attach_wake_irq() is the only caller of it, the requisite changes are easy to make. Fixes: 4990d4fe327b (PM / Wakeirq: Add automated device wake IRQ handling) Reported-by: Felipe Balbi <balbi@ti.com> Tested-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-07-07x86/irq: Retrieve irq data after locking irq_descThomas Gleixner
irq_data is protected by irq_desc->lock, so retrieving the irq chip from irq_data outside the lock is racy vs. an concurrent update. Move it into the lock held region. While at it add a comment why the vector walk does not require vector_lock. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: xiao jin <jin.xiao@intel.com> Cc: Joerg Roedel <jroedel@suse.de> Cc: Borislav Petkov <bp@suse.de> Cc: Yanmin Zhang <yanmin_zhang@linux.intel.com> Link: http://lkml.kernel.org/r/20150705171102.331320612@linutronix.de
2015-07-07x86/irq: Use proper locking in check_irq_vectors_for_cpu_disable()Thomas Gleixner
It's unsafe to examine fields in the irq descriptor w/o holding the descriptor lock. Add proper locking. While at it add a comment why the vector check can run lock less Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: xiao jin <jin.xiao@intel.com> Cc: Joerg Roedel <jroedel@suse.de> Cc: Borislav Petkov <bp@suse.de> Cc: Yanmin Zhang <yanmin_zhang@linux.intel.com> Link: http://lkml.kernel.org/r/20150705171102.236544164@linutronix.de
2015-07-07x86/irq: Plug irq vector hotplug raceThomas Gleixner
Jin debugged a nasty cpu hotplug race which results in leaking a irq vector on the newly hotplugged cpu. cpu N cpu M native_cpu_up device_shutdown do_boot_cpu free_msi_irqs start_secondary arch_teardown_msi_irqs smp_callin default_teardown_msi_irqs setup_vector_irq arch_teardown_msi_irq __setup_vector_irq native_teardown_msi_irq lock(vector_lock) destroy_irq install vectors unlock(vector_lock) lock(vector_lock) ---> __clear_irq_vector unlock(vector_lock) lock(vector_lock) set_cpu_online unlock(vector_lock) This leaves the irq vector(s) which are torn down on CPU M stale in the vector array of CPU N, because CPU M does not see CPU N online yet. There is a similar issue with concurrent newly setup interrupts. The alloc/free protection of irq descriptors does not prevent the above race, because it merily prevents interrupt descriptors from going away or changing concurrently. Prevent this by moving the call to setup_vector_irq() into the vector_lock held region which protects set_cpu_online(): cpu N cpu M native_cpu_up device_shutdown do_boot_cpu free_msi_irqs start_secondary arch_teardown_msi_irqs smp_callin default_teardown_msi_irqs lock(vector_lock) arch_teardown_msi_irq setup_vector_irq() __setup_vector_irq native_teardown_msi_irq install vectors destroy_irq set_cpu_online unlock(vector_lock) lock(vector_lock) __clear_irq_vector unlock(vector_lock) So cpu M either sees the cpu N online before clearing the vector or cpu N installs the vectors after cpu M has cleared it. Reported-by: xiao jin <jin.xiao@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Joerg Roedel <jroedel@suse.de> Cc: Borislav Petkov <bp@suse.de> Cc: Yanmin Zhang <yanmin_zhang@linux.intel.com> Link: http://lkml.kernel.org/r/20150705171102.141898931@linutronix.de
2015-07-07cxl: Fix refcounting in kernel APIMichael Neuling
Currently the kernel API AFU dev refcounting is done on context start and stop. This patch moves this refcounting to context init and release, bringing it inline with how the userspace API does it. Without this we've seen the refcounting on the AFU get out of whack between the user and kernel API usage. This causes the AFU structures to be freed when they are actually still in use. This fixes some kref warnings we've been seeing and spurious ErrIVTE IRQs. Signed-off-by: Michael Neuling <mikey@neuling.org> Acked-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-07-07x86/irq, context_tracking: Document how IRQ context tracking works and add ↵Andy Lutomirski
an RCU assertion Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/e8bdc4ed0193fb2fd130f3d6b7b8023e2ec1ab62.1435952415.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07x86/entry: Remove SCHEDULE_USER and asm/context-tracking.hAndy Lutomirski
SCHEDULE_USER is no longer used, and asm/context-tracking.h contained nothing else. Remove the header entirely. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/854e9b45f69af20e26c47099eb236321563ebcee.1435952415.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07x86/entry: Remove exception_enter() from most trap handlersAndy Lutomirski
On 64-bit kernels, we don't need it any more: we handle context tracking directly on entry from user mode and exit to user mode. On 32-bit kernels, we don't support context tracking at all, so these callbacks had no effect. Note: this doesn't change do_page_fault(). Before we do that, we need to make sure that there is no code that can page fault from kernel mode with CONTEXT_USER. The 32-bit fast system call stack argument code is the only offender I'm aware of right now. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/ae22f4dfebd799c916574089964592be218151f9.1435952415.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07x86/asm/entry/64: Migrate error and IRQ exit work to C and remove old ↵Andy Lutomirski
assembly code Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/60e90901eee611e59e958bfdbbe39969b4f88fe5.1435952415.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07x86/asm/entry/64: Simplify IRQ stack pt_regs handlingAndy Lutomirski
There's no need for both RSI and RDI to point to the original stack. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/3a0481f809dd340c7d3f54ce3fd6d66ef2a578cd.1435952415.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07x86/asm/entry/64: Save all regs on interrupt entryAndy Lutomirski
To prepare for the big rewrite of the error and interrupt exit paths, we will need pt_regs completely filled in. It's already completely filled in when error_exit runs, so rearrange interrupt handling to match it. This will slow down interrupt handling very slightly (eight instructions), but the simplification it enables will be more than worth it. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/d8a766a7f558b30e6e01352854628a2d9943460c.1435952415.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07x86/entry/64: Migrate 64-bit and compat syscalls to the new exit handlers ↵Andy Lutomirski
and remove old assembly code These need to be migrated together, as the compat case used to jump into the middle of the 64-bit exit code. Remove the old assembly code. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/d4d1d70de08ac3640badf50048a9e8f18fe2497f.1435952415.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07x86/entry/64: Really create an error-entry-from-usermode code pathAndy Lutomirski
In 539f51136500 ("x86/asm/entry/64: Disentangle error_entry/exit gsbase/ebx/usermode code"), I arranged the code slightly wrong -- IRET faults would skip the code path that was intended to execute on all error entries from user mode. Fix it up. While we're at it, make all the labels in error_entry local. This does not fix a bug, but we'll need it, and it slightly shrinks the code. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/91e17891e49fa3d61357eadc451529ad48143ee1.1435952415.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07x86/entry: Add new, comprehensible entry and exit handlers written in CAndy Lutomirski
The current x86 entry and exit code, written in a mixture of assembly and C code, is incomprehensible due to being open-coded in a lot of places without coherent documentation. It appears to work primary by luck and duct tape: i.e. obvious runtime failures were fixed on-demand, without re-thinking the design. Due to those reasons our confidence level in that code is low, and it is very difficult to incrementally improve. Add new code written in C, in preparation for simply deleting the old entry code. prepare_exit_to_usermode() is a new function that will handle all slow path exits to user mode. It is called with IRQs disabled and it leaves us in a state in which it is safe to immediately return to user mode. IRQs must not be re-enabled at any point after prepare_exit_to_usermode() returns and user mode is actually entered. (We can, of course, fail to enter user mode and treat that failure as a fresh entry to kernel mode.) All callers of do_notify_resume() will be migrated to call prepare_exit_to_usermode() instead; prepare_exit_to_usermode() needs to do everything that do_notify_resume() does today, but it also takes care of scheduling and context tracking. Unlike do_notify_resume(), it does not need to be called in a loop. syscall_return_slowpath() is exactly what it sounds like: it will be called on any syscall exit slow path. It will replace syscall_trace_leave() and it calls prepare_exit_to_usermode() on the way out. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/c57c8b87661a4152801d7d3786eac2d1a2f209dd.1435952415.git.luto@kernel.org [ Improved the changelog a bit. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07x86/entry: Add enter_from_user_mode() and use it in syscallsAndy Lutomirski
Changing the x86 context tracking hooks is dangerous because there are no good checks that we track our context correctly. Add a helper to check that we're actually in CONTEXT_USER when we enter from user mode and wire it up for syscall entries. Subsequent patches will wire this up for all non-NMI entries as well. NMIs are their own special beast and cannot currently switch overall context tracking state. Instead, they have their own special RCU hooks. This is a tiny speedup if !CONFIG_CONTEXT_TRACKING (removes a branch) and a tiny slowdown if CONFIG_CONTEXT_TRACING (adds a layer of indirection). Eventually, we should fix up the core context tracking code to supply a function that does what we want (and can be much simpler than user_exit), which will enable us to get rid of the extra call. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/853b42420066ec3fb856779cdc223a6dcb5d355b.1435952415.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07x86/traps, context_tracking: Assert that we're in CONTEXT_KERNEL in ↵Andy Lutomirski
exception entries Other than the super-atomic exception entries, all exception entries are supposed to switch our context tracking state to CONTEXT_KERNEL. Assert that they do. These assertions appear trivial at this point, as exception_enter() is the function responsible for switching context, but I'm planning on reworking x86's exception context tracking, and these assertions will help make sure that all of this code keeps working. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/20fa1ee2d943233a184aaf96ff75394d3b34dfba.1435952415.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07x86/entry: Move C entry and exit code to arch/x86/entry/common.cAndy Lutomirski
The entry and exit C helpers were confusingly scattered between ptrace.c and signal.c, even though they aren't specific to ptrace or signal handling. Move them together in a new file. This change just moves code around. It doesn't change anything. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/324d686821266544d8572423cc281f961da445f4.1435952415.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07notifiers, RCU: Assert that RCU is watching in notify_die()Andy Lutomirski
Low-level arch entries often call notify_die(), and it's easy for arch code to fail to exit an RCU quiescent state first. Assert that we're not quiescent in notify_die(). Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/1f5fe6c23d5b432a23267102f2d72b787d80fdd8.1435952415.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07context_tracking: Add ct_state() and CT_WARN_ON()Andy Lutomirski
This will let us sprinkle sanity checks around the kernel without making too much of a mess. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/5da41fb2ceb29eac671f427c67040401ba2a1fa0.1435952415.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07um: Fix do_signal() prototypeIngo Molnar
Once x86 exports its do_signal(), the prototypes will clash. Fix the clash and also improve the code a bit: remove the unnecessary kern_do_signal() indirection. This allows interrupt_end() to share the 'regs' parameter calculation. Also remove the unused return code to match x86. Minimally build and boot tested. Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Andy Lutomirski <luto@kernel.org> 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: Denys Vlasenko <dvlasenk@redhat.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Richard Weinberger <richard.weinberger@gmail.com> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/67c57eac09a589bac3c6c5ff22f9623ec55a184a.1435952415.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-07x86/entry/64/compat: Fix bad fast syscall arg failure pathAndy Lutomirski
If user code does SYSCALL32 or SYSENTER without a valid stack, then our attempt to determine the syscall args will result in a failed uaccess fault. Previously, we would try to recover by jumping to the syscall exit code, but we'd run the syscall exit work even though we never made it to the syscall entry work. Clean it up by treating the failure path as a non-syscall entry and exit pair. This fixes strace's output when running the syscall_arg_fault test. Without this fix, strace would get out of sync and would fail to associate syscall entries with syscall exits. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/903010762c07a3d67df914fea2da84b52b0f8f1d.1435952415.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>