user/sven/linux.git/include/linux, branch v3.2

security: Fix security_old_inode_init_security() when CONFIG_SECURITY is not set

2012-01-04T00:12:19Z

Commit 1e39f384bb01 ("evm: fix build problems") makes the stub version of security_old_inode_init_security() return 0 when CONFIG_SECURITY is not set. But that makes callers such as reiserfs_security_init() assume that security_old_inode_init_security() has set name, value, and len arguments properly - but security_old_inode_init_security() left them uninitialized which then results in interesting failures. Revert security_old_inode_init_security() to the old behavior of returning EOPNOTSUPP since both callers (reiserfs and ocfs2) handle this just fine. [ Also fixed the S_PRIVATE(inode) case of the actual non-stub security_old_inode_init_security() function to return EOPNOTSUPP for the same reason, as pointed out by Mimi Zohar. It got incorrectly changed to match the new function in commit fb88c2b6cbb1: "evm: fix security/security_old_init_security return code". - Linus ] Reported-by: Jorge Bastos Acked-by: James Morris Acked-by: Mimi Zohar Signed-off-by: Jan Kara Signed-off-by: Linus Torvalds

KVM: Don't automatically expose the TSC deadline timer in cpuid

2011-12-26T11:27:44Z

Unlike all of the other cpuid bits, the TSC deadline timer bit is set unconditionally, regardless of what userspace wants. This is broken in several ways: - if userspace doesn't use KVM_CREATE_IRQCHIP, and doesn't emulate the TSC deadline timer feature, a guest that uses the feature will break - live migration to older host kernels that don't support the TSC deadline timer will cause the feature to be pulled from under the guest's feet; breaking it - guests that are broken wrt the feature will fail. Fix by not enabling the feature automatically; instead report it to userspace. Because the feature depends on KVM_CREATE_IRQCHIP, which we cannot guarantee will be called, we expose it via a KVM_CAP_TSC_DEADLINE_TIMER and not KVM_GET_SUPPORTED_CPUID. Fixes the Illumos guest kernel, which uses the TSC deadline timer feature. [avi: add the KVM_CAP + documentation] Reported-by: Alexey Zaytsev Tested-by: Alexey Zaytsev Signed-off-by: Jan Kiszka Signed-off-by: Avi Kivity

VFS: Fix race between CPU hotplug and lglocks

2011-12-22T07:02:20Z

Currently, the *_global_[un]lock_online() routines are not at all synchronized with CPU hotplug. Soft-lockups detected as a consequence of this race was reported earlier at https://lkml.org/lkml/2011/8/24/185. (Thanks to Cong Meng for finding out that the root-cause of this issue is the race condition between br_write_[un]lock() and CPU hotplug, which results in the lock states getting messed up). Fixing this race by just adding {get,put}_online_cpus() at appropriate places in *_global_[un]lock_online() is not a good option, because, then suddenly br_write_[un]lock() would become blocking, whereas they have been kept as non-blocking all this time, and we would want to keep them that way. So, overall, we want to ensure 3 things: 1. br_write_lock() and br_write_unlock() must remain as non-blocking. 2. The corresponding lock and unlock of the per-cpu spinlocks must not happen for different sets of CPUs. 3. Either prevent any new CPU online operation in between this lock-unlock, or ensure that the newly onlined CPU does not proceed with its corresponding per-cpu spinlock unlocked. To achieve all this: (a) We introduce a new spinlock that is taken by the *_global_lock_online() routine and released by the *_global_unlock_online() routine. (b) We register a callback for CPU hotplug notifications, and this callback takes the same spinlock as above. (c) We maintain a bitmap which is close to the cpu_online_mask, and once it is initialized in the lock_init() code, all future updates to it are done in the callback, under the above spinlock. (d) The above bitmap is used (instead of cpu_online_mask) while locking and unlocking the per-cpu locks. The callback takes the spinlock upon the CPU_UP_PREPARE event. So, if the br_write_lock-unlock sequence is in progress, the callback keeps spinning, thus preventing the CPU online operation till the lock-unlock sequence is complete. This takes care of requirement (3). The bitmap that we maintain remains unmodified throughout the lock-unlock sequence, since all updates to it are managed by the callback, which takes the same spinlock as the one taken by the lock code and released only by the unlock routine. Combining this with (d) above, satisfies requirement (2). Overall, since we use a spinlock (mentioned in (a)) to prevent CPU hotplug operations from racing with br_write_lock-unlock, requirement (1) is also taken care of. By the way, it is to be noted that a CPU offline operation can actually run in parallel with our lock-unlock sequence, because our callback doesn't react to notifications earlier than CPU_DEAD (in order to maintain our bitmap properly). And this means, since we use our own bitmap (which is stale, on purpose) during the lock-unlock sequence, we could end up unlocking the per-cpu lock of an offline CPU (because we had locked it earlier, when the CPU was online), in order to satisfy requirement (2). But this is harmless, though it looks a bit awkward. Debugged-by: Cong Meng Signed-off-by: Srivatsa S. Bhat Signed-off-by: Al Viro Cc: stable@vger.kernel.org

Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2011-12-20T19:42:38Z

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: time/clocksource: Fix kernel-doc warnings rtc: m41t80: Workaround broken alarm functionality rtc: Expire alarms after the time is set.

time/clocksource: Fix kernel-doc warnings

2011-12-19T10:41:40Z

Fix various KernelDoc build warnings. Signed-off-by: Kusanagi Kouichi Cc: John Stultz Link: http://lkml.kernel.org/r/20111219091320.0D5AF6FC03D@msa105.auone-net.jp Signed-off-by: Ingo Molnar

Merge branch 'drm-intel-fixes' of git://people.freedesktop.org/~keithp/linux

2011-12-16T19:27:56Z

* 'drm-intel-fixes' of git://people.freedesktop.org/~keithp/linux: drm/i915/dp: Dither down to 6bpc if it makes the mode fit drm/i915: enable semaphores on per-device defaults drm/i915: don't set unpin_work if vblank_get fails drm/i915: By default, enable RC6 on IVB and SNB when reasonable iommu: Export intel_iommu_enabled to signal when iommu is in use drm/i915/sdvo: Include LVDS panels for the IS_DIGITAL check drm/i915: prevent division by zero when asking for chipset power drm/i915: add PCH info to i915_capabilities drm/i915: set the right SDVO transcoder for CPT drm/i915: no-lvds quirk for ASUS AT5NM10T-I drm/i915: Treat pre-gen4 backlight duty cycle value consistently drm/i915: Hook up Ivybridge eDP drm/i915: add multi-threaded forcewake support

Merge branch 'for-linus' of git://git.kernel.dk/linux-block

2011-12-16T18:05:14Z

* 'for-linus' of git://git.kernel.dk/linux-block: block: don't kick empty queue in blk_drain_queue() block/swim3: Locking fixes loop: Fix discard_alignment default setting cfq-iosched: fix cfq_cic_link() race confition cfq-iosched: free cic_index if blkio_alloc_blkg_stats fails cciss: fix flush cache transfer length cciss: Add IRQF_SHARED back in for the non-MSI(X) interrupt handler loop: fix loop block driver discard and encryption comment block: initialize request_queue's numa node during

iommu: Export intel_iommu_enabled to signal when iommu is in use

2011-12-16T16:49:57Z

In i915 driver, we do not enable either rc6 or semaphores on SNB when dmar is enabled. The new 'intel_iommu_enabled' variable signals when the iommu code is in operation. Cc: Ted Phelps Cc: Peter Cc: Lukas Hejtmanek Cc: Andrew Lutomirski CC: Daniel Vetter Cc: Eugeni Dodonov Signed-off-by: Keith Packard

linux/log2.h: Fix rounddown_pow_of_two(1)

2011-12-13T06:06:55Z

Exactly like roundup_pow_of_two(1), the rounddown version was buggy for the case of a compile-time constant '1' argument. Probably because it originated from the same code, sharing history with the roundup version from before the bugfix (for that one, see commit 1a06a52ee1b0: "Fix roundup_pow_of_two(1)"). However, unlike the roundup version, the fix for rounddown is to just remove the broken special case entirely. It's simply not needed - the generic code 1UL << ilog2(n) does the right thing for the constant '1' argment too. The only reason roundup needed that special case was because rounding up does so by subtracting one from the argument (and then adding one to the result) causing the obvious problems with "ilog2(0)". But rounddown doesn't do any of that, since ilog2() naturally truncates (ie "rounds down") to the right rounded down value. And without the ilog2(0) case, there's no reason for the special case that had the wrong value. tl;dr: rounddown_pow_of_two(1) should be 1, not 0. Acked-by: Dmitry Torokhov Cc: stable@kernel.org Signed-off-by: Linus Torvalds

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc

2011-12-13T04:06:13Z

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc: mmc: core: Fix deadlock when the CONFIG_MMC_UNSAFE_RESUME is not defined mmc: sdhci-s3c: Remove old and misprototyped suspend operations mmc: tmio: fix clock gating on platforms with a .set_pwr() method mmc: sh_mmcif: fix clock gating on platforms with a .down_pwr() method mmc: core: Fix typo at mmc_card_sleep mmc: core: Fix power_off_notify during suspend mmc: core: Fix setting power notify state variable for non-eMMC mmc: core: Add quirk for long data read time mmc: Add module.h include to sdhci-cns3xxx.c mmc: mxcmmc: fix falling back to PIO mmc: omap_hsmmc: DMA unmap only once in case of MMC error