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2015-12-07virtio_ring: shadow available ring flags & indexVenkatesh Srinivas1-12/+34
Improves cacheline transfer flow of available ring header. Virtqueues are implemented as a pair of rings, one producer->consumer avail ring and one consumer->producer used ring; preceding the avail ring in memory are two contiguous u16 fields -- avail->flags and avail->idx. A producer posts work by writing to avail->idx and a consumer reads avail->idx. The flags and idx fields only need to be written by a producer CPU and only read by a consumer CPU; when the producer and consumer are running on different CPUs and the virtio_ring code is structured to only have source writes/sink reads, we can continuously transfer the avail header cacheline between 'M' states between cores. This flow optimizes core -> core bandwidth on certain CPUs. (see: "Software Optimization Guide for AMD Family 15h Processors", Section 11.6; similar language appears in the 10h guide and should apply to CPUs w/ exclusive caches, using LLC as a transfer cache) Unfortunately the existing virtio_ring code issued reads to the avail->idx and read-modify-writes to avail->flags on the producer. This change shadows the flags and index fields in producer memory; the vring code now reads from the shadows and only ever writes to avail->flags and avail->idx, allowing the cacheline to transfer core -> core optimally. In a concurrent version of vring_bench, the time required for 10,000,000 buffer checkout/returns was reduced by ~2% (average across many runs) on an AMD Piledriver (15h) CPU: (w/o shadowing): Performance counter stats for './vring_bench': 5,451,082,016 L1-dcache-loads ... 2.221477739 seconds time elapsed (w/ shadowing): Performance counter stats for './vring_bench': 5,405,701,361 L1-dcache-loads ... 2.168405376 seconds time elapsed The further away (in a NUMA sense) virtio producers and consumers are from each other, the more we expect to benefit. Physical implementations of virtio devices and implementations of virtio where the consumer polls vring avail indexes (vhost) should also benefit. Signed-off-by: Venkatesh Srinivas <venkateshs@google.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-12-07virtio: Do not drop __GFP_HIGH in alloc_indirectMichal Hocko1-1/+1
b92b1b89a33c ("virtio: force vring descriptors to be allocated from lowmem") tried to exclude highmem pages for descriptors so it cleared __GFP_HIGHMEM from a given gfp mask. The patch also cleared __GFP_HIGH which doesn't make much sense for this fix because __GFP_HIGH only controls access to memory reserves and it doesn't have any influence on the zone selection. Some of the call paths use GFP_ATOMIC and dropping __GFP_HIGH will reduce their changes for success because the lack of access to memory reserves. Signed-off-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Mel Gorman <mgorman@techsingularity.net>
2015-12-07vhost: replace % with & on data pathMichael S. Tsirkin1-3/+3
We know vring num is a power of 2, so use & to mask the high bits. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-12-07tools/virtio: fix byteswap logicMichael S. Tsirkin1-7/+13
commit cf561f0d2eb74574ad9985a2feab134267a9d298 ("virtio: introduce virtio_is_little_endian() helper") changed byteswap logic to skip feature bit checks for LE platforms, but didn't update tools/virtio, so vring_bench started failing. Update the copy under tools/virtio/ (TODO: find a way to avoid this code duplication). Cc: Greg Kurz <gkurz@linux.vnet.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-12-07tools/virtio: move list macro stubsMichael S. Tsirkin2-6/+6
Makes them more generally available. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-12-07virtio: fix memory leak of virtio ida cache layersSuman Anna1-0/+1
The virtio core uses a static ida named virtio_index_ida for assigning index numbers to virtio devices during registration. The ida core may allocate some internal idr cache layers and an ida bitmap upon any ida allocation, and all these layers are truely freed only upon the ida destruction. The virtio_index_ida is not destroyed at present, leading to a memory leak when using the virtio core as a module and atleast one virtio device is registered and unregistered. Fix this by invoking ida_destroy() in the virtio core module exit. Cc: stable@vger.kernel.org Signed-off-by: Suman Anna <s-anna@ti.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-12-07vhost: relax log address alignmentMichael S. Tsirkin1-1/+1
commit 5d9a07b0de512b77bf28d2401e5fe3351f00a240 ("vhost: relax used address alignment") fixed the alignment for the used virtual address, but not for the physical address used for logging. That's a mistake: alignment should clearly be the same for virtual and physical addresses, Cc: stable@vger.kernel.org Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-12-07virtio-net: Stop doing DMA from the stackMichael S. Tsirkin1-15/+19
Once virtio starts using the DMA API, we won't be able to safely DMA from the stack. virtio-net does a couple of config DMA requests from small stack buffers -- switch to using dynamically-allocated memory. This should have no effect on any performance-critical code paths. Reported-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Tested-by: Andy Lutomirski <luto@kernel.org>
2015-12-06Linux 4.4-rc4v4.4-rc4Linus Torvalds1-1/+1
2015-12-06staging/lustre: remove IOC_LIBCFS_PING_TEST ioctlJames Simmons2-18/+0
The ioctl IOC_LIBCFS_PING_TEST has not been used in ages. The recent nidstring changes which moved all the nidstring operations from libcfs to the LNet layer but this ioctl code was still using an nidstring operation that was causing a circular dependency loop between libcfs and LNet. Signed-off-by: James Simmons <jsimmons@infradead.org> Signed-off-by: Oleg Drokin <green@linuxhacker.ru> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-12-06Merge branch 'for-linus' of ↵Linus Torvalds4-31/+15
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs fixes from Al Viro: "A couple of fixes (-stable fodder) + dead code removal after the overlayfs fix. I agree that it's better to separate from the fix part to make backporting easier, but IMO it's not worth delaying said dead code removal until the next window" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: Don't reset ->total_link_count on nested calls of vfs_path_lookup() ovl: get rid of the dead code left from broken (and disabled) optimizations ovl: fix permission checking for setattr
2015-12-06Don't reset ->total_link_count on nested calls of vfs_path_lookup()Al Viro1-1/+0
we already zero it on outermost set_nameidata(), so initialization in path_init() is pointless and wrong. The same DoS exists on pre-4.2 kernels, but there a slightly different fix will be needed. Cc: stable@vger.kernel.org # v4.2 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-06ovl: get rid of the dead code left from broken (and disabled) optimizationsAl Viro3-26/+11
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-06ovl: fix permission checking for setattrMiklos Szeredi1-4/+4
[Al Viro] The bug is in being too enthusiastic about optimizing ->setattr() away - instead of "copy verbatim with metadata" + "chmod/chown/utimes" (with the former being always safe and the latter failing in case of insufficient permissions) it tries to combine these two. Note that copyup itself will have to do ->setattr() anyway; _that_ is where the elevated capabilities are right. Having these two ->setattr() (one to set verbatim copy of metadata, another to do what overlayfs ->setattr() had been asked to do in the first place) combined is where it breaks. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Cc: <stable@vger.kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-06Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds5-15/+45
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Thomas Gleixner: "This updates contains the following changes: - Fix a signal handling regression in the bit wait functions. - Avoid false positive warnings in the wakeup path. - Initialize the scheduler root domain properly. - Handle gtime calculations in proc/$PID/stat proper. - Add more documentation for the barriers in try_to_wake_up(). - Fix a subtle race in try_to_wake_up() which might cause a task to be scheduled on two cpus - Compile static helper function only when it is used" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/core: Fix an SMP ordering race in try_to_wake_up() vs. schedule() sched/core: Better document the try_to_wake_up() barriers sched/cputime: Fix invalid gtime in proc sched/core: Clear the root_domain cpumasks in init_rootdomain() sched/core: Remove false-positive warning from wake_up_process() sched/wait: Fix signal handling in bit wait helpers sched/rt: Hide the push_irq_work_func() declaration
2015-12-06Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds12-36/+54
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thoma Gleixner: "Another round of fixes for x86: - Move the initialization of the microcode driver to late_initcall to make sure everything that init function needs is available. - Make sure that lockdep knows about interrupts being off in the entry code before calling into c-code. - Undo the cpu hotplug init delay regression. - Use the proper conditionals in the mpx instruction decoder. - Fixup restart_syscall for x32 tasks. - Fix the hugepage regression on PAE kernels which was introduced with the latest PAT changes" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/signal: Fix restart_syscall number for x32 tasks x86/mpx: Fix instruction decoder condition x86/mm: Fix regression with huge pages on PAE x86 smpboot: Re-enable init_udelay=0 by default on modern CPUs x86/entry/64: Fix irqflag tracing wrt context tracking x86/microcode: Initialize the driver late when facilities are up
2015-12-06Merge tag 'scsi-fixes' of ↵Linus Torvalds19-70/+129
git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi Pull SCSI fixes from James Bottomley: "This is quite a bumper crop of fixes: three from Arnd correcting various build issues in some configurations, a lock recursion in qla2xxx. Two potentially exploitable issues in hpsa and mvsas, a potential null deref in st, a revert of a bdi registration fix that turned out to cause even more problems, a set of fixes to allow people who only defined MPT2SAS to still work after the mpt2/mpt3sas merger and a couple of fixes for issues turned up by the hyper-v storvsc driver" * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: mpt3sas: fix Kconfig dependency problem for mpt2sas back compatibility Revert "scsi: Fix a bdi reregistration race" mpt3sas: Add dummy Kconfig option for backwards compatibility Fix a memory leak in scsi_host_dev_release() block/sd: Fix device-imposed transfer length limits scsi_debug: fix prevent_allow+verify regressions MAINTAINERS: Add myself as co-maintainer of the SCSI subsystem. sd: Make discard granularity match logical block size when LBPRZ=1 scsi: hpsa: select CONFIG_SCSI_SAS_ATTR scsi: advansys needs ISA dma api for ISA support scsi_sysfs: protect against double execution of __scsi_remove_device() st: fix potential null pointer dereference. scsi: report 'INQUIRY result too short' once per host advansys: fix big-endian builds qla2xxx: Fix rwlock recursion hpsa: logical vs bitwise AND typo mvsas: don't allow negative timeouts mpt3sas: Fix use sas_is_tlr_enabled API before enabling MPI2_SCSIIO_CONTROL_TLR_ON flag
2015-12-05Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linuxLinus Torvalds57-331/+735
Pull drm fixes from Dave Airlie: "A bunch of change across the board, the main things are some vblank fallout in radeon and nouveau required some work, but I think this should fix it all. There is also one drm fix for an oops in vmwgfx with how we pass the drm master around. The rest is just some amdgpu, i915, imx and rockchip fixes. Probably more than I'd like at this point, but hopefully things settle down now" * 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (40 commits) drm/amdgpu: Fixup hw vblank counter/ts for new drm_update_vblank_count() (v3) drm/radeon: Fixup hw vblank counter/ts for new drm_update_vblank_count() (v2) drm/radeon: Retry DDC probing on DVI on failure if we got an HPD interrupt drm/amdgpu: add spin lock to protect freed list in vm (v2) drm/amdgpu: partially revert "drm/amdgpu: fix VM_CONTEXT*_PAGE_TABLE_END_ADDR" v2 drm/amdgpu: take a BO reference for the user fence drm/amdgpu: take a BO reference in the display code drm/amdgpu: set snooped flags only on system addresses v2 drm/nouveau: Fix pre-nv50 pageflip events (v4) drm: Fix an unwanted master inheritance v2 drm/amdgpu: fix race condition in amd_sched_entity_push_job drm/amdgpu: add err check for pin userptr drm/i915: take a power domain reference while checking the HDMI live status drm/i915: add MISSING_CASE to a few port/aux power domain helpers drm/i915/ddi: fix intel_display_port_aux_power_domain() after HDMI detect drm/i915: Introduce a gmbus power domain drm/i915: Clean up AUX power domain handling drm/rockchip: Use CRTC vblank event interface drm/rockchip: Fix module autoload for OF platform driver drm/rockchip: vop: fix window origin calculation ...
2015-12-05Merge branch 'linus' of ↵Linus Torvalds3-3/+4
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto fixes from Herbert Xu: "This fixes a couple of crypto drivers that were using memcmp to verify authentication tags. They now use crypto_memneq instead" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: crypto: talitos - Fix timing leak in ESP ICV verification crypto: nx - Fix timing leak in GCM and CCM decryption
2015-12-05x86/signal: Fix restart_syscall number for x32 tasksDmitry V. Levin1-7/+10
When restarting a syscall with regs->ax == -ERESTART_RESTARTBLOCK, regs->ax is assigned to a restart_syscall number. For x32 tasks, this syscall number must have __X32_SYSCALL_BIT set, otherwise it will be an x86_64 syscall number instead of a valid x32 syscall number. This issue has been there since the introduction of x32. Reported-by: strace/tests/restart_syscall.test Reported-and-tested-by: Elvira Khabirova <lineprinter0@gmail.com> Signed-off-by: Dmitry V. Levin <ldv@altlinux.org> Cc: Elvira Khabirova <lineprinter0@gmail.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20151130215436.GA25996@altlinux.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-12-05x86/mpx: Fix instruction decoder conditionDave Hansen1-3/+3
MPX decodes instructions in order to tell which bounds register was violated. Part of this decoding involves looking at the "REX prefix" which is a special instrucion prefix used to retrofit support for new registers in to old instructions. The X86_REX_*() macros are defined to return actual bit values: #define X86_REX_R(rex) ((rex) & 4) *not* boolean values. However, the MPX code was checking for them like they were booleans. This might have led to us mis-decoding the "REX prefix" and giving false information out to userspace about bounds violations. X86_REX_B() actually is bit 1, so this is really only broken for the X86_REX_X() case. Fix the conditionals up to tolerate the non-boolean values. Fixes: fcc7ffd67991 "x86, mpx: Decode MPX instruction to get bound violation information" Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: x86@kernel.org Cc: Dave Hansen <dave@sr71.net> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20151201003113.D800C1E0@viggo.jf.intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-12-05Merge branch 'drm-fixes-4.4' of git://people.freedesktop.org/~agd5f/linux ↵Dave Airlie30-91/+387
into drm-next A few more last minute fixes for 4.4 on top of my pull request from earlier this week. The big change here is a vblank regression fix due to commit 4dfd6486 "drm: Use vblank timestamps to guesstimate how many vblanks were missed". Beyond that, a hotplug fix and a few VM fixes. * 'drm-fixes-4.4' of git://people.freedesktop.org/~agd5f/linux: drm/amdgpu: Fixup hw vblank counter/ts for new drm_update_vblank_count() (v3) drm/radeon: Fixup hw vblank counter/ts for new drm_update_vblank_count() (v2) drm/radeon: Retry DDC probing on DVI on failure if we got an HPD interrupt drm/amdgpu: add spin lock to protect freed list in vm (v2) drm/amdgpu: partially revert "drm/amdgpu: fix VM_CONTEXT*_PAGE_TABLE_END_ADDR" v2 drm/amdgpu: take a BO reference for the user fence drm/amdgpu: take a BO reference in the display code drm/amdgpu: set snooped flags only on system addresses v2 drm/amdgpu: fix race condition in amd_sched_entity_push_job drm/amdgpu: add err check for pin userptr add blacklist for thinkpad T40p drm/amdgpu: fix VM page table reference counting drm/amdgpu: fix userptr flags check
2015-12-04Merge branch 'for-linus' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client Pull Ceph fix from Sage Weil: "This addresses a refcounting bug that leads to a use-after-free" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: rbd: don't put snap_context twice in rbd_queue_workfn()
2015-12-04drm/amdgpu: Fixup hw vblank counter/ts for new drm_update_vblank_count() (v3)Alex Deucher6-30/+140
commit 4dfd6486 "drm: Use vblank timestamps to guesstimate how many vblanks were missed" introduced in Linux 4.4-rc1 makes the drm core more fragile to drivers which don't update hw vblank counters and vblank timestamps in sync with firing of the vblank irq and essentially at leading edge of vblank. This exposed a problem with radeon-kms/amdgpu-kms which do not satisfy above requirements: The vblank irq fires a few scanlines before start of vblank, but programmed pageflips complete at start of vblank and vblank timestamps update at start of vblank, whereas the hw vblank counter increments only later, at start of vsync. This leads to problems like off by one errors for vblank counter updates, vblank counters apparently going backwards or vblank timestamps apparently having time going backwards. The net result is stuttering of graphics in games, or little hangs, as well as total failure of timing sensitive applications. See bug #93147 for an example of the regression on Linux 4.4-rc: https://bugs.freedesktop.org/show_bug.cgi?id=93147 This patch tries to align all above events better from the viewpoint of the drm core / of external callers to fix the problem: 1. The apparent start of vblank is shifted a few scanlines earlier, so the vblank irq now always happens after start of this extended vblank interval and thereby drm_update_vblank_count() always samples the updated vblank count and timestamp of the new vblank interval. To achieve this, the reporting of scanout positions by radeon_get_crtc_scanoutpos() now operates as if the vblank starts radeon_crtc->lb_vblank_lead_lines before the real start of the hw vblank interval. This means that the vblank timestamps which are based on these scanout positions will now update at this earlier start of vblank. 2. The driver->get_vblank_counter() function will bump the returned vblank count as read from the hw by +1 if the query happens after the shifted earlier start of the vblank, but before the real hw increment at start of vsync, so the counter appears to increment at start of vblank in sync with the timestamp update. 3. Calls from vblank irq-context and regular non-irq calls are now treated identical, always simulating the shifted vblank start, to avoid inconsistent results for queries happening from vblank irq vs. happening from drm_vblank_enable() or vblank_disable_fn(). 4. The radeon_flip_work_func will delay mmio programming a pageflip until the start of the real vblank iff it happens to execute inside the shifted earlier start of the vblank, so pageflips now also appear to execute at start of the shifted vblank, in sync with vblank counter and timestamp updates. This to avoid some races between updates of vblank count and timestamps that are used for swap scheduling and pageflip execution which could cause pageflips to execute before the scheduled target vblank. The lb_vblank_lead_lines "fudge" value is calculated as the size of the display controllers line buffer in scanlines for the given video mode: Vblank irq's are triggered by the line buffer logic when the line buffer refill for a video frame ends, ie. when the line buffer source read position enters the hw vblank. This means that a vblank irq could fire at most as many scanlines before the current reported scanout position of the crtc timing generator as the number of scanlines the line buffer can maximally hold for a given video mode. This patch has been successfully tested on a RV730 card with DCE-3 display engine and on a evergreen card with DCE-4 display engine, in single-display and dual-display configuration, with different video modes. A similar patch is needed for amdgpu-kms to fix the same problem. Limitations: - Maybe replace the udelay() in the flip_work_func() by a suitable usleep_range() for a bit better efficiency? Will try that. - Line buffer sizes in pixels are hard-coded on < DCE-4 to a value i just guessed to be high enough to work ok, lacking info on the true sizes atm. Probably fixes: fdo#93147 Port of Mario's radeon fix to amdgpu. Signed-off-by: Alex Deucher <alexander.deucher@amd.com> (v1) Reviewed-by: Mario Kleiner <mario.kleiner.de@gmail.com> (v2) Refine amdgpu_flip_work_func() for better efficiency. In amdgpu_flip_work_func, replace the busy waiting udelay(5) with event lock held by a more performance and energy efficient usleep_range() until at least predicted true start of hw vblank, with some slack for scheduler happiness. Release the event lock during waits to not delay other outputs in doing their stuff, as the waiting can last up to 200 usecs in some cases. Also small fix to code comment and formatting in that function. (v2) Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com> (v3) Fix crash in crtc disabled case
2015-12-04Merge branch 'libnvdimm-fixes' of ↵Linus Torvalds4-53/+76
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm fixes from Dan Williams: - NFIT parsing regression fixes from Linda. The nvdimm hot-add implementation merged in 4.4-rc1 interpreted the specification in a way that breaks actual HPE platforms. We are also closing the loop with the ACPI Working Group to get this clarification added to the spec. - Andy pointed out that his laptop without nvdimm resources is loading the e820-nvdimm module by default, fix that up to only load the module when an e820-type-12 range is present. * 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: nfit: Adjust for different _FIT and NFIT headers nfit: Fix the check for a successful NFIT merge nfit: Account for table size length variation libnvdimm, e820: skip module loading when no type-12
2015-12-04Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds9-89/+107
Pull ARM KVM fixes from Paolo Bonzini: - a series of fixes to deal with the aliasing between the sp and xzr register - a fix for the cache flush fix that went in -rc3 * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: ARM/arm64: KVM: correct PTE uncachedness check arm64: KVM: Get rid of old vcpu_reg() arm64: KVM: Correctly handle zero register in system register accesses arm64: KVM: Remove const from struct sys_reg_params arm64: KVM: Correctly handle zero register during MMIO
2015-12-04drm/radeon: Fixup hw vblank counter/ts for new drm_update_vblank_count() (v2)Mario Kleiner9-29/+164
commit 4dfd6486 "drm: Use vblank timestamps to guesstimate how many vblanks were missed" introduced in Linux 4.4-rc1 makes the drm core more fragile to drivers which don't update hw vblank counters and vblank timestamps in sync with firing of the vblank irq and essentially at leading edge of vblank. This exposed a problem with radeon-kms/amdgpu-kms which do not satisfy above requirements: The vblank irq fires a few scanlines before start of vblank, but programmed pageflips complete at start of vblank and vblank timestamps update at start of vblank, whereas the hw vblank counter increments only later, at start of vsync. This leads to problems like off by one errors for vblank counter updates, vblank counters apparently going backwards or vblank timestamps apparently having time going backwards. The net result is stuttering of graphics in games, or little hangs, as well as total failure of timing sensitive applications. See bug #93147 for an example of the regression on Linux 4.4-rc: https://bugs.freedesktop.org/show_bug.cgi?id=93147 This patch tries to align all above events better from the viewpoint of the drm core / of external callers to fix the problem: 1. The apparent start of vblank is shifted a few scanlines earlier, so the vblank irq now always happens after start of this extended vblank interval and thereby drm_update_vblank_count() always samples the updated vblank count and timestamp of the new vblank interval. To achieve this, the reporting of scanout positions by radeon_get_crtc_scanoutpos() now operates as if the vblank starts radeon_crtc->lb_vblank_lead_lines before the real start of the hw vblank interval. This means that the vblank timestamps which are based on these scanout positions will now update at this earlier start of vblank. 2. The driver->get_vblank_counter() function will bump the returned vblank count as read from the hw by +1 if the query happens after the shifted earlier start of the vblank, but before the real hw increment at start of vsync, so the counter appears to increment at start of vblank in sync with the timestamp update. 3. Calls from vblank irq-context and regular non-irq calls are now treated identical, always simulating the shifted vblank start, to avoid inconsistent results for queries happening from vblank irq vs. happening from drm_vblank_enable() or vblank_disable_fn(). 4. The radeon_flip_work_func will delay mmio programming a pageflip until the start of the real vblank iff it happens to execute inside the shifted earlier start of the vblank, so pageflips now also appear to execute at start of the shifted vblank, in sync with vblank counter and timestamp updates. This to avoid some races between updates of vblank count and timestamps that are used for swap scheduling and pageflip execution which could cause pageflips to execute before the scheduled target vblank. The lb_vblank_lead_lines "fudge" value is calculated as the size of the display controllers line buffer in scanlines for the given video mode: Vblank irq's are triggered by the line buffer logic when the line buffer refill for a video frame ends, ie. when the line buffer source read position enters the hw vblank. This means that a vblank irq could fire at most as many scanlines before the current reported scanout position of the crtc timing generator as the number of scanlines the line buffer can maximally hold for a given video mode. This patch has been successfully tested on a RV730 card with DCE-3 display engine and on a evergreen card with DCE-4 display engine, in single-display and dual-display configuration, with different video modes. A similar patch is needed for amdgpu-kms to fix the same problem. Limitations: - Line buffer sizes in pixels are hard-coded on < DCE-4 to a value i just guessed to be high enough to work ok, lacking info on the true sizes atm. Fixes: fdo#93147 Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Michel Dänzer <michel.daenzer@amd.com> Cc: Harry Wentland <Harry.Wentland@amd.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> (v1) Tested-by: Dave Witbrodt <dawitbro@sbcglobal.net> (v2) Refine radeon_flip_work_func() for better efficiency: In radeon_flip_work_func, replace the busy waiting udelay(5) with event lock held by a more performance and energy efficient usleep_range() until at least predicted true start of hw vblank, with some slack for scheduler happiness. Release the event lock during waits to not delay other outputs in doing their stuff, as the waiting can last up to 200 usecs in some cases. Retested on DCE-3 and DCE-4 to verify it still works nicely. (v2) Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2015-12-04drm/radeon: Retry DDC probing on DVI on failure if we got an HPD interruptLyude10-12/+32
HPD signals on DVI ports can be fired off before the pins required for DDC probing actually make contact, due to the pins for HPD making contact first. This results in a HPD signal being asserted but DDC probing failing, resulting in hotplugging occasionally failing. This is somewhat rare on most cards (depending on what angle you plug the DVI connector in), but on some cards it happens constantly. The Radeon R5 on the machine used for testing this patch for instance, runs into this issue just about every time I try to hotplug a DVI monitor and as a result hotplugging almost never works. Rescheduling the hotplug work for a second when we run into an HPD signal with a failing DDC probe usually gives enough time for the rest of the connector's pins to make contact, and fixes this issue. Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Lyude <cpaul@redhat.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2015-12-04drm/amdgpu: add spin lock to protect freed list in vm (v2)jimqu2-3/+15
there is a protection fault about freed list when OCL test. add a spin lock to protect it. v2: drop changes in vm_fini Signed-off-by: JimQu <jim.qu@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com>
2015-12-04drm/amdgpu: partially revert "drm/amdgpu: fix ↵Christian König2-2/+2
VM_CONTEXT*_PAGE_TABLE_END_ADDR" v2 The gtt_end is already inclusive, we don't need to subtract one here. v2 (chk): keep the fix for the VM code, cause here it really applies. Signed-off-by: Christian König <christian.koenig@amd.com> Signed-off-by: Anatoli Antonovitch <anatoli.antonovitch@amd.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Cc: stable@vger.kernel.org Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2015-12-04drm/amdgpu: take a BO reference for the user fenceChristian König1-2/+4
No need for a GEM reference here. Reviewed-by: Michel Dänzer <michel.daenzer@amd.com> Signed-off-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2015-12-04drm/amdgpu: take a BO reference in the display codeChristian König1-3/+3
No need for the GEM reference here. Reviewed-by: Michel Dänzer <michel.daenzer@amd.com> Signed-off-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2015-12-04Merge tag 'kvm-arm-for-v4.4-rc4' of ↵Paolo Bonzini9-89/+107
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master KVM/ARM fixes for v4.4-rc4 - A series of fixes to deal with the aliasing between the sp and xzr register - A fix for the cache flush fix that went in -rc3
2015-12-04drm/amdgpu: set snooped flags only on system addresses v2Christian König1-3/+4
Not necessary for VRAM. v2: no need to check if ttm is NULL. Signed-off-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2015-12-04Merge tag 'sound-4.4-rc4' of ↵Linus Torvalds28-107/+247
git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound Pull sound fixes from Takashi Iwai: "This time we've got a larger number of updates, mainly from ASoC world. The only significant LOCs found here are for Realtek codecs, where most of changes are quite systematic replacements. There are also a few fixes in ASoC core side: one is the PM call order fix to ensure the DPAM resume working properly. Another is the proper cleanup call after freeing DAPM widgets, and the correction of the wrong callback set in topology API. The rest are a wide range of driver-specific small fixes, including HD-audio" * tag 'sound-4.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (35 commits) ALSA: hda - Add Conexant CX8200 (14f1:2008) codec entry ALSA: hda - Correct codec names for 14f1:50f1 and 14f1:50f3 ALSA: hda - Skip ELD notification during system suspend ASoC: core: Change power state before rechecking endpoint ASoC: fix kernel-doc warnings in sound/soc/soc-ops.c ASoC: rt5645: Add dmi_system_id "Google Terra" ASoC: rockchip: Fix incorrect VDW value for 24 bit ASoC: fsl: clarify ac97 dependency ASoC: Intel: Skylake: fix memory leak ASoC: davinci-mcasp: Fix master capture only mode ASoC: es8328: Fix shifts for mixer switches ASoC: rt5645: Add dmi_system_id "Google Wizpig" ASoC: sti: set player private data ASoC: sti: rename ST proprietary DT properties ASoC: sti: remove wrong error message ASoC: Intel: Skylake: Add I2C depends for SKL machine ASoC: topology: fix info callback for TLV byte control ASoC: rt5670: fix wrong bit def for pll src ASoC: nau8825: add pm function ASoC: rt5645: Add struct dmi_system_id "Google Edgar" for Chrome OS ...
2015-12-04Merge tag 'pm+acpi-4.4-rc4' of ↵Linus Torvalds10-27/+40
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management and ACPI fixes from Rafael Wysocki: "These fix a recent regression in the ACPI PCI host bridge initialization code, clean up some recent changes (generic power domains framework, ACPI AML debugger support), fix three older but annoying bugs (PCI power management. generic power domains framework, cpufreq) and a build problem (device properties framework), and update a stale MAINTAINERS entry (ACPI backlight driver). Specifics: - Fix a regression in the ACPI PCI host bridge initialization code introduced by the recent consolidation of the host bridge handling on x86 and ia64 that forgot to take one special piece of code related to NUMA on x86 into account (Liu Jiang). - Improve the Kconfig help description of the new ACPI AML debugger support option to avoid possible confusion (Peter Zijlstra). - Remove a piece of code in the generic power domains framework that should have been removed by one of the recent commits modifying that code (Ulf Hansson). - Reduce the log level of a PCI PM message that generates a lot of false-positive log noise for some drivers and improve the message itself while at it (Imre Deak). - Fix the OF-based domain lookup code in the generic power domains framework to make it drop references to DT nodes correctly (Eric Anholt). - Prevent the cpufreq core from setting the policy back to the default after a CPU offline/online cycle for cpufreq drivers providing the ->setpolicy callback (Srinivas Pandruvada). - Fix a build problem for CONFIG_ACPI unset in the device properties framework (Hanjun Guo). - Fix a stale file path in the ACPI backlight driver entry in MAINTAINERS (Dan Carpenter)" * tag 'pm+acpi-4.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: PM / Domains: Fix bad of_node_put() in failure paths of genpd_dev_pm_attach() cpufreq: use last policy after online for drivers with ->setpolicy PCI / PM: Tune down retryable runtime suspend error messages PM / Domains: Validate cases of a non-bound driver in genpd governor MAINTAINERS: ACPI / video: update a file name in drivers/acpi/ ACPI / property: fix compile error for acpi_node_get_property_reference() when CONFIG_ACPI=n x86/PCI/ACPI: Fix regression caused by commit 4d6b4e69a245 ACPI: Better describe ACPI_DEBUGGER
2015-12-04ARM/arm64: KVM: correct PTE uncachedness checkArd Biesheuvel1-2/+2
Commit e6fab5442345 ("ARM/arm64: KVM: test properly for a PTE's uncachedness") modified the logic to test whether a HYP or stage-2 mapping needs flushing, from [incorrectly] interpreting the page table attributes to [incorrectly] checking whether the PFN that backs the mapping is covered by host system RAM. The PFN number is part of the output of the translation, not the input, so we have to use pte_pfn() on the contents of the PTE, not __phys_to_pfn() on the HYP virtual address or stage-2 intermediate physical address. Fixes: e6fab5442345 ("ARM/arm64: KVM: test properly for a PTE's uncachedness") Cc: stable@vger.kernel.org Tested-by: Pavel Fedin <p.fedin@samsung.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-12-04arm64: KVM: Get rid of old vcpu_reg()Pavel Fedin3-19/+14
Using oldstyle vcpu_reg() accessor is proven to be inappropriate and unsafe on ARM64. This patch converts the rest of use cases to new accessors and completely removes vcpu_reg() on ARM64. Signed-off-by: Pavel Fedin <p.fedin@samsung.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-12-04arm64: KVM: Correctly handle zero register in system register accessesPavel Fedin3-48/+45
System register accesses also use zero register for Rt == 31, and therefore using it will also result in getting SP value instead. This patch makes them also using new accessors, introduced by the previous patch. Since register value is no longer directly associated with storage inside vCPU context structure, we introduce a dedicated storage for it in struct sys_reg_params. This refactor also gets rid of "massive hack" in kvm_handle_cp_64(). Signed-off-by: Pavel Fedin <p.fedin@samsung.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-12-04arm64: KVM: Remove const from struct sys_reg_paramsPavel Fedin3-21/+21
Further rework is going to introduce a dedicated storage for transfer register value in struct sys_reg_params. Before doing this we have to remove 'const' modifiers from it in all accessor functions and their callers. Signed-off-by: Pavel Fedin <p.fedin@samsung.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-12-04arm64: KVM: Correctly handle zero register during MMIOPavel Fedin3-2/+28
On ARM64 register index of 31 corresponds to both zero register and SP. However, all memory access instructions, use ZR as transfer register. SP is used only as a base register in indirect memory addressing, or by register-register arithmetics, which cannot be trapped here. Correct emulation is achieved by introducing new register accessor functions, which can do special handling for reg_num == 31. These new accessors intentionally do not rely on old vcpu_reg() on ARM64, because it is to be removed. Since the affected code is shared by both ARM flavours, implementations of these accessors are also added to ARM32 code. This patch fixes setting MMIO register to a random value (actually SP) instead of zero by something like: *((volatile int *)reg) = 0; compilers tend to generate "str wzr, [xx]" here [Marc: Fixed 32bit splat] Signed-off-by: Pavel Fedin <p.fedin@samsung.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-12-04rbd: don't put snap_context twice in rbd_queue_workfn()Ilya Dryomov1-0/+1
Commit 4e752f0ab0e8 ("rbd: access snapshot context and mapping size safely") moved ceph_get_snap_context() out of rbd_img_request_create() and into rbd_queue_workfn(), adding a ceph_put_snap_context() to the error path in rbd_queue_workfn(). However, rbd_img_request_create() consumes a ref on snapc, so calling ceph_put_snap_context() after a successful rbd_img_request_create() leads to an extra put. Fix it. Cc: stable@vger.kernel.org # 3.18+ Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Reviewed-by: Josh Durgin <jdurgin@redhat.com>
2015-12-04Merge branches 'pm-domains' and 'pm-cpufreq'Rafael J. Wysocki4-9/+12
* pm-domains: PM / Domains: Fix bad of_node_put() in failure paths of genpd_dev_pm_attach() PM / Domains: Validate cases of a non-bound driver in genpd governor * pm-cpufreq: cpufreq: use last policy after online for drivers with ->setpolicy
2015-12-04Merge branches 'acpica', 'acpi-video' and 'device-properties'Rafael J. Wysocki3-5/+5
* acpica: ACPI: Better describe ACPI_DEBUGGER * acpi-video: MAINTAINERS: ACPI / video: update a file name in drivers/acpi/ * device-properties: ACPI / property: fix compile error for acpi_node_get_property_reference() when CONFIG_ACPI=n
2015-12-04Merge branches 'acpi-pci' and 'pm-pci'Rafael J. Wysocki9828-240585/+479223
* acpi-pci: x86/PCI/ACPI: Fix regression caused by commit 4d6b4e69a245 * pm-pci: PCI / PM: Tune down retryable runtime suspend error messages
2015-12-04sched/core: Fix an SMP ordering race in try_to_wake_up() vs. schedule()Peter Zijlstra1-0/+19
Oleg noticed that its possible to falsely observe p->on_cpu == 0 such that we'll prematurely continue with the wakeup and effectively run p on two CPUs at the same time. Even though the overlap is very limited; the task is in the middle of being scheduled out; it could still result in corruption of the scheduler data structures. CPU0 CPU1 set_current_state(...) <preempt_schedule> context_switch(X, Y) prepare_lock_switch(Y) Y->on_cpu = 1; finish_lock_switch(X) store_release(X->on_cpu, 0); try_to_wake_up(X) LOCK(p->pi_lock); t = X->on_cpu; // 0 context_switch(Y, X) prepare_lock_switch(X) X->on_cpu = 1; finish_lock_switch(Y) store_release(Y->on_cpu, 0); </preempt_schedule> schedule(); deactivate_task(X); X->on_rq = 0; if (X->on_rq) // false if (t) while (X->on_cpu) cpu_relax(); context_switch(X, ..) finish_lock_switch(X) store_release(X->on_cpu, 0); Avoid the load of X->on_cpu being hoisted over the X->on_rq load. Reported-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-12-04sched/core: Better document the try_to_wake_up() barriersPeter Zijlstra2-1/+10
Explain how the control dependency and smp_rmb() end up providing ACQUIRE semantics and pair with smp_store_release() in finish_lock_switch(). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-12-04sched/cputime: Fix invalid gtime in procHiroshi Shimamoto1-0/+3
/proc/stats shows invalid gtime when the thread is running in guest. When vtime accounting is not enabled, we cannot get a valid delta. The delta is calculated with now - tsk->vtime_snap, but tsk->vtime_snap is only updated when vtime accounting is runtime enabled. This patch makes task_gtime() just return gtime without computing the buggy non-existing tickless delta when vtime accounting is not enabled. Use context_tracking_is_enabled() to check if vtime is accounting on some cpu, in which case only we need to check the tickless delta. This way we fix the gtime value regression on machines not running nohz full. The kernel config contains CONFIG_VIRT_CPU_ACCOUNTING_GEN=y and CONFIG_NO_HZ_FULL_ALL=n and boot without nohz_full. I ran and stop a busy loop in VM and see the gtime in host. Dump the 43rd field which shows the gtime in every second: # while :; do awk '{print $3" "$43}' /proc/3955/task/4014/stat; sleep 1; done S 4348 R 7064566 R 7064766 R 7064967 R 7065168 S 4759 S 4759 During running busy loop, it returns large value. After applying this patch, we can see right gtime. # while :; do awk '{print $3" "$43}' /proc/10913/task/10956/stat; sleep 1; done S 5338 R 5365 R 5465 R 5566 R 5666 S 5726 S 5726 Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Chris Metcalf <cmetcalf@ezchip.com> Cc: Christoph Lameter <cl@linux.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luiz Capitulino <lcapitulino@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.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> Link: http://lkml.kernel.org/r/1447948054-28668-2-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-12-04sched/core: Clear the root_domain cpumasks in init_rootdomain()Xunlei Pang1-4/+4
root_domain::rto_mask allocated through alloc_cpumask_var() contains garbage data, this may cause problems. For instance, When doing pull_rt_task(), it may do useless iterations if rto_mask retains some extra garbage bits. Worse still, this violates the isolated domain rule for clustered scheduling using cpuset, because the tasks(with all the cpus allowed) belongs to one root domain can be pulled away into another root domain. The patch cleans the garbage by using zalloc_cpumask_var() instead of alloc_cpumask_var() for root_domain::rto_mask allocation, thereby addressing the issues. Do the same thing for root_domain's other cpumask memembers: dlo_mask, span, and online. Signed-off-by: Xunlei Pang <xlpang@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1449057179-29321-1-git-send-email-xlpang@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-12-04sched/core: Remove false-positive warning from wake_up_process()Sasha Levin1-1/+0
Because wakeups can (fundamentally) be late, a task might not be in the expected state. Therefore testing against a task's state is racy, and can yield false positives. Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: oleg@redhat.com Fixes: 9067ac85d533 ("wake_up_process() should be never used to wakeup a TASK_STOPPED/TRACED task") Link: http://lkml.kernel.org/r/1448933660-23082-1-git-send-email-sasha.levin@oracle.com Signed-off-by: Ingo Molnar <mingo@kernel.org>