Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1392828

[PATCH 4.5 047/200] futex: Acknowledge a new waiter in counter before plist

Show all headers | View raw

4.5-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Davidlohr Bueso <dave@stgolabs.net>

commit fe1bce9e2107ba3a8faffe572483b6974201a0e6 upstream.

Otherwise an incoming waker on the dest hash bucket can miss
the waiter adding itself to the plist during the lockless
check optimization (small window but still the correct way
of doing this); similarly to the decrement counterpart.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: bigeasy@linutronix.de
Cc: dvhart@infradead.org
Link: http://lkml.kernel.org/r/1461208164-29150-1-git-send-email-dave@stgolabs.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 kernel/futex.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -1452,8 +1452,8 @@ void requeue_futex(struct futex_q *q, st
 	if (likely(&hb1->chain != &hb2->chain)) {
 		plist_del(&q->list, &hb1->chain);
 		hb_waiters_dec(hb1);
-		plist_add(&q->list, &hb2->chain);
 		hb_waiters_inc(hb2);
+		plist_add(&q->list, &hb2->chain);
 		q->lock_ptr = &hb2->lock;
 	}
 	get_futex_key_refs(key2);

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH 4.5 000/200] 4.5.3-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 064/200] powerpc: scan_features() updates incorrect bits for REAL_LE Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 048/200] drm/nouveau/core: use vzalloc for allocating ramht Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 073/200] pinctrl: single: Fix pcs_parse_bits_in_pinctrl_entry to use __ffs than ffs Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 006/200] kvm: x86: do not leak guest xcr0 into host interrupt handlers Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 117/200] [media] videobuf2-core: Check user space planes array in dqbuf Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 067/200] nl80211: check netlink protocol in socket release notification Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 114/200] ASoC: rt5640: Correct the digital interface data select Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 120/200] cxl: Keep IRQ mappings on context teardown Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 066/200] powerpc: Update TM user feature bits in scan_features() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 116/200] [media] media: vb2: Fix regression on poll() for RW mode Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 062/200] crypto: talitos - fix crash in talitos_cra_init() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 096/200] drm/amdkfd: uninitialized variable in dbgdev_wave_control_set_registers() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 070/200] Input: pmic8xxx-pwrkey - fix algorithm for converting trigger delay Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 118/200] [media] videobuf2-v4l2: Verify planes array in buffer dequeueing Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
    Re: [PATCH 4.5 118/200] [media] videobuf2-v4l2: Verify planes array  in buffer dequeueing Mauro Carvalho Chehab <mchehab@osg.samsung.com> - 2016-05-11 18:40 +0200
  [PATCH 4.5 119/200] [media] v4l2-dv-timings.h: fix polarity for 4k formats Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 107/200] ACPICA / Interpreter: Fix a regression triggered because of wrong Linux ECDT support Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 112/200] ASoC: ssm4567: Reset device before regcache_sync() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 061/200] crypto: sha1-mb - use corrcet pointer while completing jobs Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 106/200] i2c: exynos5: Fix possible ABBA deadlock by keeping I2C clock prepared Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 047/200] futex: Acknowledge a new waiter in counter before plist Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 056/200] s390/pci: add extra padding to function measurement block Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 057/200] iwlwifi: pcie: lower the debug level for RSA semaphore access Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 105/200] i2c: cpm: Fix build break due to incompatible pointer types Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 063/200] crypto: talitos - fix AEAD tcrypt tests Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 009/200] ARM: dts: am43xx: fix edma memcpy channel allocation Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 115/200] [media] vb2-memops: Fix over allocation of frame vectors Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 075/200] iommu/dma: Restore scatterlist offsets correctly Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:20 +0200
  [PATCH 4.5 042/200] ALSA: pcxhr: Fix missing mutex unlock Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 022/200] usb: gadget: f_fs: Fix use-after-free Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 025/200] lib: lz4: fixed zram with lz4 on big endian machines Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 004/200] efi/arm64: Dont apply MEMBLOCK_NOMAP to UEFI memory map mapping Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 024/200] dm cache metadata: fix cmd_read_lock() acquiring write lock Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 029/200] dmaengine: hsu: correct residue calculation of active descriptor Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 032/200] dmaengine: pxa_dma: fix the maximum requestor line Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 015/200] xhci: resume USB 3 roothub first Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 028/200] dmaengine: hsu: correct use of channel status register Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 016/200] usb: host: xhci: add a new quirk XHCI_NO_64BIT_SUPPORT Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 014/200] usb: xhci: applying XHCI_PME_STUCK_QUIRK to Intel BXT B0 host Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 005/200] x86/mce: Avoid using object after free in genpool Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 002/200] block: partition: initialize percpuref before sending out KOBJ_ADD Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 031/200] dmaengine: edma: Remove dynamic TPTC power management feature Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 040/200] ALSA: hda - Keep powering up ADCs on Cirrus codecs Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 033/200] mtd: nand: pxa3xx_nand: fix dmaengine initialization Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 026/200] debugfs: Make automount point inodes permanently empty Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 044/200] ALSA: hda - Update BCLK also at hotplug for i915 HSW/BDW Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 011/200] ARM: OMAP2: Fix up interconnect barrier initialization for DRA7 Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 018/200] usb: xhci: fix wild pointers in xhci_mem_cleanup Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 030/200] dmaengine: omap-dma: Fix polled channel completion detection and handling Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 023/200] dm cache metadata: fix READ_LOCK macros and cleanup WRITE_LOCK macros Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 043/200] ALSA: hda - Add dock support for ThinkPad X260 Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 027/200] dmaengine: dw: fix master selection Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 001/200] mmc: block: Use the mmc host device index as the mmcblk device index Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:30 +0200
  [PATCH 4.5 010/200] ARM: mvebu: Correct unit address for linksys Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 03:40 +0200
  Re: [PATCH 4.5 000/200] 4.5.3-stable review Guenter Roeck <linux@roeck-us.net> - 2016-05-03 09:50 +0200
    Re: [PATCH 4.5 000/200] 4.5.3-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 20:30 +0200
      Re: [PATCH 4.5 000/200] 4.5.3-stable review Guenter Roeck <linux@roeck-us.net> - 2016-05-04 04:30 +0200
  Re: [PATCH 4.5 000/200] 4.5.3-stable review Shuah Khan <shuahkh@osg.samsung.com> - 2016-05-03 17:00 +0200
    Re: [PATCH 4.5 000/200] 4.5.3-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-03 20:20 +0200

csiph-web