Skip to content

L
linux
Switch branch/tag
  1. 09 Feb, 2012 13 commits
    • Russell King's avatar
      ARM: omap: fix oops in drivers/video/omap2/dss/dpi.c · 40410715
      Russell King authored 
      When a PMIC is not found, this driver is unable to obtain its
'vdds_dsi_reg' regulator.  Even through its initialization function
fails, other code still calls its enable function, which fails to
check whether it has this regulator before asking for it to be enabled.

This fixes the oops, however a better fix would be to sort out the
upper layers to prevent them calling into a module which failed to
initialize.

Unable to handle kernel NULL pointer dereference at virtual address 00000038
pgd = c0004000
[00000038] *pgd=00000000
Internal error: Oops: 5 [#1] PREEMPT
Modules linked in:
CPU: 0    Not tainted  (3.3.0-rc2+ #228)
PC is at regulator_enable+0x10/0x70
LR is at omapdss_dpi_display_enable+0x54/0x15c
pc : [<c01b9a08>]    lr : [<c01af994>]    psr: 60000013
sp : c181fd90  ip : c181fdb0  fp : c181fdac
r10: c042eff0  r9 : 00000060  r8 : c044a164
r7 : c042c0e4  r6 : c042bd60  r5 : 00000000  r4 : c042bd60
r3 : c084de48  r2 : c181e000  r1 : c042bd60  r0 : 00000000
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
Control: 10c5387d  Table: 80004019  DAC: 00000015
Process swapper (pid: 1, stack limit = 0xc181e2e8)
Stack: (0xc181fd90 to 0xc1820000)
fd80:                                     c001754c c042bd60 00000000 c042bd60
fda0: c181fdcc c181fdb0 c01af994 c01b9a04 c0016104 c042bd60 c042bd60 c044a338
fdc0: c181fdec c181fdd0 c01b5ed0 c01af94c c042bd60 c042bd60 c1aa8000 c1aa8a0c
fde0: c181fe04 c181fdf0 c01b5f54 c01b5ea8 c02fc18c c042bd60 c181fe3c c181fe08
fe00: c01b2a18 c01b5f48 c01aed14 c02fc160 c01df8ec 00000002 c042bd60 00000003
fe20: c042bd60 c1aa8000 c1aa8a0c c042eff8 c181fe84 c181fe40 c01b3874 c01b29fc
fe40: c042eff8 00000000 c042f000 c0449db8 c044ed78 00000000 c181fe74 c042eff8
fe60: c042eff8 c0449db8 c0449db8 c044ed78 00000000 00000000 c181fe94 c181fe88
fe80: c01e452c c01b35e8 c181feb4 c181fe98 c01e2fdc c01e4518 c042eff8 c0449db8
fea0: c0449db8 c181fef0 c181fecc c181feb8 c01e3104 c01e2f48 c042eff8 c042f02c
fec0: c181feec c181fed0 c01e3190 c01e30c0 c01e311c 00000000 c01e311c c0449db8
fee0: c181ff14 c181fef0 c01e1998 c01e3128 c18330a8 c1892290 c04165e8 c0449db8
ff00: c0449db8 c1ab60c0 c181ff24 c181ff18 c01e2e28 c01e194c c181ff54 c181ff28
ff20: c01e2218 c01e2e14 c039afed c181ff38 c04165e8 c041660c c0449db8 00000013
ff40: 00000000 c03ffdb8 c181ff7c c181ff58 c01e384c c01e217c c181ff7c c04165e8
ff60: c041660c c003a37c 00000013 00000000 c181ff8c c181ff80 c01e488c c01e3790
ff80: c181ff9c c181ff90 c03ffdcc c01e484c c181ffdc c181ffa0 c0008798 c03ffdc4
ffa0: c181ffc4 c181ffb0 c0056440 c0187810 c003a37c c04165e8 c041660c c003a37c
ffc0: 00000013 00000000 00000000 00000000 c181fff4 c181ffe0 c03ea284 c0008708
ffe0: 00000000 c03ea208 00000000 c181fff8 c003a37c c03ea214 1073cec0 01f7ee08
Backtrace:
[<c01b99f8>] (regulator_enable+0x0/0x70) from [<c01af994>] (omapdss_dpi_display_enable+0x54/0x15c)
 r6:c042bd60 r5:00000000 r4:c042bd60
[<c01af940>] (omapdss_dpi_display_enable+0x0/0x15c) from [<c01b5ed0>] (generic_dpi_panel_power_on+0x34/0x78)
 r6:c044a338 r5:c042bd60 r4:c042bd60
[<c01b5e9c>] (generic_dpi_panel_power_on+0x0/0x78) from [<c01b5f54>] (generic_dpi_panel_enable+0x18/0x28)
 r7:c1aa8a0c r6:c1aa8000 r5:c042bd60 r4:c042bd60
[<c01b5f3c>] (generic_dpi_panel_enable+0x0/0x28) from [<c01b2a18>] (omapfb_init_display+0x28/0x150)
 r4:c042bd60
[<c01b29f0>] (omapfb_init_display+0x0/0x150) from [<c01b3874>] (omapfb_probe+0x298/0x318)
 r8:c042eff8 r7:c1aa8a0c r6:c1aa8000 r5:c042bd60 r4:00000003
[<c01b35dc>] (omapfb_probe+0x0/0x318) from [<c01e452c>] (platform_drv_probe+0x20/0x24)
[<c01e450c>] (platform_drv_probe+0x0/0x24) from [<c01e2fdc>] (really_probe+0xa0/0x178)
[<c01e2f3c>] (really_probe+0x0/0x178) from [<c01e3104>] (driver_probe_device+0x50/0x68)
 r7:c181fef0 r6:c0449db8 r5:c0449db8 r4:c042eff8
[<c01e30b4>] (driver_probe_device+0x0/0x68) from [<c01e3190>] (__driver_attach+0x74/0x98)
 r5:c042f02c r4:c042eff8
[<c01e311c>] (__driver_attach+0x0/0x98) from [<c01e1998>] (bus_for_each_dev+0x58/0x98)
 r6:c0449db8 r5:c01e311c r4:00000000
[<c01e1940>] (bus_for_each_dev+0x0/0x98) from [<c01e2e28>] (driver_attach+0x20/0x28)
 r7:c1ab60c0 r6:c0449db8 r5:c0449db8 r4:c04165e8
[<c01e2e08>] (driver_attach+0x0/0x28) from [<c01e2218>] (bus_add_driver+0xa8/0x22c)
[<c01e2170>] (bus_add_driver+0x0/0x22c) from [<c01e384c>] (driver_register+0xc8/0x154)
[<c01e3784>] (driver_register+0x0/0x154) from [<c01e488c>] (platform_driver_register+0x4c/0x60)
 r8:00000000 r7:00000013 r6:c003a37c r5:c041660c r4:c04165e8
[<c01e4840>] (platform_driver_register+0x0/0x60) from [<c03ffdcc>] (omapfb_init+0x14/0x34)
[<c03ffdb8>] (omapfb_init+0x0/0x34) from [<c0008798>] (do_one_initcall+0x9c/0x164)
[<c00086fc>] (do_one_initcall+0x0/0x164) from [<c03ea284>] (kernel_init+0x7c/0x120)
[<c03ea208>] (kernel_init+0x0/0x120) from [<c003a37c>] (do_exit+0x0/0x2d8)
 r5:c03ea208 r4:00000000
Code: e1a0c00d e92dd870 e24cb004 e24dd004 (e5906038)
---[ end trace 9e2474c2e193b223 ]---
Acked-by: default avatarTony Lindgren <tony@atomide.com>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
      40410715
    • Russell King's avatar
      ARM: omap: fix oops in arch/arm/mach-omap2/vp.c when pmic is not found · d980e0f8
      Russell King authored 
      When the PMIC is not found, voltdm->pmic will be NULL.  vp.c's
initialization function tries to dereferences this, which causes an
oops:

Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = c0004000
[00000000] *pgd=00000000
Internal error: Oops: 5 [#1] PREEMPT
Modules linked in:
CPU: 0    Not tainted  (3.3.0-rc2+ #204)
PC is at omap_vp_init+0x5c/0x15c
LR is at omap_vp_init+0x58/0x15c
pc : [<c03db880>]    lr : [<c03db87c>]    psr: 60000013
sp : c181ff30  ip : c181ff68  fp : c181ff64
r10: c0407808  r9 : c040786c  r8 : c0407814
r7 : c0026868  r6 : c00264fc  r5 : c040ad6c  r4 : 00000000
r3 : 00000040  r2 : 000032c8  r1 : 0000fa00  r0 : 000032c8
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
Control: 10c5387d  Table: 80004019  DAC: 00000015
Process swapper (pid: 1, stack limit = 0xc181e2e8)
Stack: (0xc181ff30 to 0xc1820000)
ff20:                                     c0381d00 c02e9c6d c0383582 c040786c
ff40: c040ad6c c00264fc c0026868 c0407814 00000000 c03d9de4 c181ff8c c181ff68
ff60: c03db448 c03db830 c02e982c c03fdfb8 c03fe004 c0039988 00000013 00000000
ff80: c181ff9c c181ff90 c03d9df8 c03db390 c181ffdc c181ffa0 c0008798 c03d9df0
ffa0: c181ffc4 c181ffb0 c0055a44 c0187050 c0039988 c03fdfb8 c03fe004 c0039988
ffc0: 00000013 00000000 00000000 00000000 c181fff4 c181ffe0 c03d1284 c0008708
ffe0: 00000000 c03d1208 00000000 c181fff8 c0039988 c03d1214 1077ce40 01f7ee08
Backtrace:
[<c03db824>] (omap_vp_init+0x0/0x15c) from [<c03db448>] (omap_voltage_late_init+0xc4/0xfc)
[<c03db384>] (omap_voltage_late_init+0x0/0xfc) from [<c03d9df8>] (omap2_common_pm_late_init+0x14/0x54)
 r8:00000000 r7:00000013 r6:c0039988 r5:c03fe004 r4:c03fdfb8
[<c03d9de4>] (omap2_common_pm_late_init+0x0/0x54) from [<c0008798>] (do_one_initcall+0x9c/0x164)
[<c00086fc>] (do_one_initcall+0x0/0x164) from [<c03d1284>] (kernel_init+0x7c/0x120)
[<c03d1208>] (kernel_init+0x0/0x120) from [<c0039988>] (do_exit+0x0/0x2cc)
 r5:c03d1208 r4:00000000
Code: e5ca300b e5900034 ebf69027 e5994024 (e5941000)
---[ end trace aed617dddaf32c3d ]---
Kernel panic - not syncing: Attempted to kill init!
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
      d980e0f8
    • Linus Torvalds's avatar
      Linux 3.3-rc3 · d65b4e98
      Linus Torvalds authored
      d65b4e98
    • Linus Torvalds's avatar
      Merge branch 'iommu/fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu · 63082402
      Linus Torvalds authored 
      One patch fixes an bug in the ARM/MSM IOMMU code which returned sucess
in the unmap function even when an error occured and the other patch
adds a workaround into the AMD IOMMU driver to better handle broken IVRS
ACPI tables (this patch fixes the case when a device is not listed in
the table but actually translated by the iommu).

* 'iommu/fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/msm: Fix error handling in msm_iommu_unmap()
  iommu/amd: Work around broken IVRS tables
      63082402
    • Linus Torvalds's avatar
      Merge branch '3.3-rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending · 19e75ed4
      Linus Torvalds authored 
      This series contains pending target bug-fixes and cleanups for v3.3-rc3
that have been addressed the past weeks in lio-core.git.

Some of the highlights include:

 - Fix handling for control CDBs with data greater than PAGE_SIZE (andy)
 - Use IP_FREEBIND for iscsi-target to address network portal creation
   issues with systemd (dax)
 - Allow PERSISTENT RESERVE IN for non-reservation holder (marco)
 - Fix iblock se_dev_attrib.unmap_granularity (marco)
 - Fix unsupported WRITE_SAME sense payload handling (martin)
 - Add workaround for zero-length control CDB handling (nab)
 - Fix discovery with INADDR_ANY and IN6ADDR_ANY_INIT (nab)
 - Fix target_submit_cmd() exception handling (nab)
 - Return correct ASC for unimplemented VPD pages (roland)
 - Don't zero pages used for data buffers (roland)
 - Fix return code of core_tpg_.*_lun (sebastian)

* '3.3-rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (26 commits)
  target: Fix unsupported WRITE_SAME sense payload
  iscsi: use IP_FREEBIND socket option
  iblock: fix handling of large requests
  target: handle empty string writes in sysfs
  iscsi_target: in_aton needs linux/inet.h
  target: Fix iblock se_dev_attrib.unmap_granularity
  target: Fix target_submit_cmd() exception handling
  target: Change target_submit_cmd() to return void
  target: accept REQUEST_SENSE with 18bytes
  target: Fail INQUIRY commands with EVPD==0 but PAGE CODE!=0
  target: Return correct ASC for unimplemented VPD pages
  iscsi-target: Fix discovery with INADDR_ANY and IN6ADDR_ANY_INIT
  target: Allow control CDBs with data > 1 page
  iscsi-target: Fix up a few assignments
  iscsi-target: make one-bit bitfields unsigned
  iscsi-target: Fix double list_add with iscsit_alloc_buffs reject
  iscsi-target: Fix reject release handling in iscsit_free_cmd()
  target: fix return code of core_tpg_.*_lun
  target: use save/restore lock primitive in core_dec_lacl_count()
  target: avoid multiple outputs in scsi_dump_inquiry()
  ...
      19e75ed4
    • Linus Torvalds's avatar
      Merge tag 'md-3.3-fixes' of git://neil.brown.name/md · 4d39aa1b
      Linus Torvalds authored 
      Some simple md-related fixes.

1/ two small fixes to ensure we handle an interrupted resync properly.
2/ avoid loading the bitmap multiple times in dm-raid

* tag 'md-3.3-fixes' of git://neil.brown.name/md:
  md: two small fixes to handling interrupt resync.
  Prevent DM RAID from loading bitmap twice.
      4d39aa1b
    • Linus Torvalds's avatar
      Merge tag 'spi-for-linus' of git://git.secretlab.ca/git/linux-2.6 · 4a68d54c
      Linus Torvalds authored 
      SPI bug fixes for v3.3-rc2

Minor SPI device driver changes.  A rename of the pch_spi_pcidev symbol
that merely eliminates a modpost warning, and a Kconfig change to allow
the Samsung spi driver to build on EXYNOS.

* tag 'spi-for-linus' of git://git.secretlab.ca/git/linux-2.6:
  spi-topcliff-pch: rename pch_spi_pcidev to pch_spi_pcidev_driver
  spi: Add spi-s3c64xx driver dependency on ARCH_EXYNOS4
      4a68d54c
    • Linus Torvalds's avatar
      Merge branch 'akpm' (Andrew's tree) · 15a46353
      Linus Torvalds authored 
      Five fixes

* branch 'akpm':
  pcmcia: fix socket refcount decrementing on each resume
  mm: fix UP THP spin_is_locked BUGs
  drivers/leds/leds-lm3530.c: fix setting pltfm->als_vmax
  mm: compaction: check for overlapping nodes during isolation for migration
  nilfs2: avoid overflowing segment numbers in nilfs_ioctl_clean_segments()
      15a46353
    • Russell King's avatar
      pcmcia: fix socket refcount decrementing on each resume · 025e4ab3
      Russell King authored 
      This fixes a memory-corrupting bug: not only does it cause the warning,
but as a result of dropping the refcount to zero, it causes the
pcmcia_socket0 device structure to be freed while it still has
references, causing slab caches corruption.  A fatal oops quickly
follows this warning - often even just a 'dmesg' following the warning
causes the kernel to oops.

While testing suspend/resume on an ARM device with PCMCIA support, and a
CF card inserted, I found that after five suspend and resumes, the
kernel would complain, and shortly die after with slab corruption.

  WARNING: at include/linux/kref.h:41 kobject_get+0x28/0x50()

As the message doesn't give a clue about which kobject, and the built-in
debugging in drivers/base/power/main.c happens too late, this was added
right before each get_device():

  printk("%s: %p [%s] %u\n", __func__, dev, kobject_name(&dev->kobj), atomic_read(&dev->kobj.kref.refcount));

and on the 3rd s2ram cycle, the following behaviour observed:

On the 3rd suspend/resume cycle:

  dpm_prepare: c1a0d998 [pcmcia_socket0] 3
  dpm_suspend: c1a0d998 [pcmcia_socket0] 3
  dpm_suspend_noirq: c1a0d998 [pcmcia_socket0] 3
  dpm_resume_noirq: c1a0d998 [pcmcia_socket0] 3
  dpm_resume: c1a0d998 [pcmcia_socket0] 3
  dpm_complete: c1a0d998 [pcmcia_socket0] 2

4th:

  dpm_prepare: c1a0d998 [pcmcia_socket0] 2
  dpm_suspend: c1a0d998 [pcmcia_socket0] 2
  dpm_suspend_noirq: c1a0d998 [pcmcia_socket0] 2
  dpm_resume_noirq: c1a0d998 [pcmcia_socket0] 2
  dpm_resume: c1a0d998 [pcmcia_socket0] 2
  dpm_complete: c1a0d998 [pcmcia_socket0] 1

5th:

  dpm_prepare: c1a0d998 [pcmcia_socket0] 1
  dpm_suspend: c1a0d998 [pcmcia_socket0] 1
  dpm_suspend_noirq: c1a0d998 [pcmcia_socket0] 1
  dpm_resume_noirq: c1a0d998 [pcmcia_socket0] 1
  dpm_resume: c1a0d998 [pcmcia_socket0] 1
  dpm_complete: c1a0d998 [pcmcia_socket0] 0
  ------------[ cut here ]------------
  WARNING: at include/linux/kref.h:41 kobject_get+0x28/0x50()
  Modules linked in: ucb1x00_core
  Backtrace:
  [<c0212090>] (dump_backtrace+0x0/0x110) from [<c04799dc>] (dump_stack+0x18/0x1c)
  [<c04799c4>] (dump_stack+0x0/0x1c) from [<c021cba0>] (warn_slowpath_common+0x50/0x68)
  [<c021cb50>] (warn_slowpath_common+0x0/0x68) from [<c021cbdc>] (warn_slowpath_null+0x24/0x28)
  [<c021cbb8>] (warn_slowpath_null+0x0/0x28) from [<c0335374>] (kobject_get+0x28/0x50)
  [<c033534c>] (kobject_get+0x0/0x50) from [<c03804f4>] (get_device+0x1c/0x24)
  [<c0388c90>] (dpm_complete+0x0/0x1a0) from [<c0389cc0>] (dpm_resume_end+0x1c/0x20)
  ...

Looking at commit 7b24e798 ("pcmcia: split up central event handler"),
the following change was made to cs.c:

                return 0;
        }
 #endif
-
-       send_event(skt, CS_EVENT_PM_RESUME, CS_EVENT_PRI_LOW);
+       if (!(skt->state & SOCKET_CARDBUS) && (skt->callback))
+               skt->callback->early_resume(skt);
        return 0;
 }

And the corresponding change in ds.c is from:

-static int ds_event(struct pcmcia_socket *skt, event_t event, int priority)
-{
-       struct pcmcia_socket *s = pcmcia_get_socket(skt);
...
-       switch (event) {
...
-       case CS_EVENT_PM_RESUME:
-               if (verify_cis_cache(skt) != 0) {
-                       dev_dbg(&skt->dev, "cis mismatch - different card\n");
-                       /* first, remove the card */
-                       ds_event(skt, CS_EVENT_CARD_REMOVAL, CS_EVENT_PRI_HIGH);
-                       mutex_lock(&s->ops_mutex);
-                       destroy_cis_cache(skt);
-                       kfree(skt->fake_cis);
-                       skt->fake_cis = NULL;
-                       s->functions = 0;
-                       mutex_unlock(&s->ops_mutex);
-                       /* now, add the new card */
-                       ds_event(skt, CS_EVENT_CARD_INSERTION,
-                                CS_EVENT_PRI_LOW);
-               }
-               break;
...
-    }

-    pcmcia_put_socket(s);

-    return 0;
-} /* ds_event */

to:

+static int pcmcia_bus_early_resume(struct pcmcia_socket *skt)
+{
+       if (!verify_cis_cache(skt)) {
+               pcmcia_put_socket(skt);
+               return 0;
+       }

+       dev_dbg(&skt->dev, "cis mismatch - different card\n");

+       /* first, remove the card */
+       pcmcia_bus_remove(skt);
+       mutex_lock(&skt->ops_mutex);
+       destroy_cis_cache(skt);
+       kfree(skt->fake_cis);
+       skt->fake_cis = NULL;
+       skt->functions = 0;
+       mutex_unlock(&skt->ops_mutex);

+       /* now, add the new card */
+       pcmcia_bus_add(skt);
+       return 0;
+}

As can be seen, the original function called pcmcia_get_socket() and
pcmcia_put_socket() around the guts, whereas the replacement code
calls pcmcia_put_socket() only in one path.  This creates an imbalance
in the refcounting.

Testing with pcmcia_put_socket() put removed shows that the bug is gone:

  dpm_suspend: c1a10998 [pcmcia_socket0] 5
  dpm_suspend_noirq: c1a10998 [pcmcia_socket0] 5
  dpm_resume_noirq: c1a10998 [pcmcia_socket0] 5
  dpm_resume: c1a10998 [pcmcia_socket0] 5
  dpm_complete: c1a10998 [pcmcia_socket0] 5
Tested-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      025e4ab3
    • Hugh Dickins's avatar
      mm: fix UP THP spin_is_locked BUGs · b9980cdc
      Hugh Dickins authored 
      Fix CONFIG_TRANSPARENT_HUGEPAGE=y CONFIG_SMP=n CONFIG_DEBUG_VM=y
CONFIG_DEBUG_SPINLOCK=n kernel: spin_is_locked() is then always false,
and so triggers some BUGs in Transparent HugePage codepaths.

asm-generic/bug.h mentions this problem, and provides a WARN_ON_SMP(x);
but being too lazy to add VM_BUG_ON_SMP, BUG_ON_SMP, WARN_ON_SMP_ONCE,
VM_WARN_ON_SMP_ONCE, just test NR_CPUS != 1 in the existing VM_BUG_ONs.
Signed-off-by: default avatarHugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      b9980cdc
    • Axel Lin's avatar
      drivers/leds/leds-lm3530.c: fix setting pltfm->als_vmax · ec44fd42
      Axel Lin authored 
      In current code, pltfm->als_vmin is set to LM3530_ALS_WINDOW_mV and
pltfm->als_vmax is 0.  This does not make sense.  I think what we want
here is setting pltfm->als_vmax to LM3530_ALS_WINDOW_mV.

Both als_vmin and als_vmax local variables will be set to
pltfm->als_vmin and pltfm->als_vmax by a few lines latter.  Thus also
remove a redundant assignment for als_vmin and als_vmax in this patch.
Signed-off-by: default avatarAxel Lin <axel.lin@gmail.com>
Cc: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
Acked-by: default avatarMilo(Woogyom) Kim <milo.kim@ti.com>
Tested-by: default avatarMilo(Woogyom) Kim <milo.kim@ti.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      ec44fd42
    • Mel Gorman's avatar
      mm: compaction: check for overlapping nodes during isolation for migration · dc908600
      Mel Gorman authored 
      When isolating pages for migration, migration starts at the start of a
zone while the free scanner starts at the end of the zone.  Migration
avoids entering a new zone by never going beyond the free scanned.

Unfortunately, in very rare cases nodes can overlap.  When this happens,
migration isolates pages without the LRU lock held, corrupting lists
which will trigger errors in reclaim or during page free such as in the
following oops

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
  IP: [<ffffffff810f795c>] free_pcppages_bulk+0xcc/0x450
  PGD 1dda554067 PUD 1e1cb58067 PMD 0
  Oops: 0000 [#1] SMP
  CPU 37
  Pid: 17088, comm: memcg_process_s Tainted: G            X
  RIP: free_pcppages_bulk+0xcc/0x450
  Process memcg_process_s (pid: 17088, threadinfo ffff881c2926e000, task ffff881c2926c0c0)
  Call Trace:
    free_hot_cold_page+0x17e/0x1f0
    __pagevec_free+0x90/0xb0
    release_pages+0x22a/0x260
    pagevec_lru_move_fn+0xf3/0x110
    putback_lru_page+0x66/0xe0
    unmap_and_move+0x156/0x180
    migrate_pages+0x9e/0x1b0
    compact_zone+0x1f3/0x2f0
    compact_zone_order+0xa2/0xe0
    try_to_compact_pages+0xdf/0x110
    __alloc_pages_direct_compact+0xee/0x1c0
    __alloc_pages_slowpath+0x370/0x830
    __alloc_pages_nodemask+0x1b1/0x1c0
    alloc_pages_vma+0x9b/0x160
    do_huge_pmd_anonymous_page+0x160/0x270
    do_page_fault+0x207/0x4c0
    page_fault+0x25/0x30

The "X" in the taint flag means that external modules were loaded but but
is unrelated to the bug triggering.  The real problem was because the PFN
layout looks like this

  Zone PFN ranges:
    DMA      0x00000010 -> 0x00001000
    DMA32    0x00001000 -> 0x00100000
    Normal   0x00100000 -> 0x01e80000
  Movable zone start PFN for each node
  early_node_map[14] active PFN ranges
      0: 0x00000010 -> 0x0000009b
      0: 0x00000100 -> 0x0007a1ec
      0: 0x0007a354 -> 0x0007a379
      0: 0x0007f7ff -> 0x0007f800
      0: 0x00100000 -> 0x00680000
      1: 0x00680000 -> 0x00e80000
      0: 0x00e80000 -> 0x01080000
      1: 0x01080000 -> 0x01280000
      0: 0x01280000 -> 0x01480000
      1: 0x01480000 -> 0x01680000
      0: 0x01680000 -> 0x01880000
      1: 0x01880000 -> 0x01a80000
      0: 0x01a80000 -> 0x01c80000
      1: 0x01c80000 -> 0x01e80000

The fix is straight-forward.  isolate_migratepages() has to make a
similar check to isolate_freepage to ensure that it never isolates pages
from a zone it does not hold the LRU lock for.

This was discovered in a 3.0-based kernel but it affects 3.1.x, 3.2.x
and current mainline.
Signed-off-by: default avatarMel Gorman <mgorman@suse.de>
Acked-by: default avatarMichal Nazarewicz <mina86@mina86.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      dc908600
    • Xi Wang's avatar
      nilfs2: avoid overflowing segment numbers in nilfs_ioctl_clean_segments() · 1ecd3c7e
      Xi Wang authored 
      nsegs is read from userspace.  Limit its value and avoid overflowing nsegs
* sizeof(__u64) in the subsequent call to memdup_user().

This patch complements 481fe17e ("nilfs2: potential integer overflow
in nilfs_ioctl_clean_segments()").
Signed-off-by: default avatarXi Wang <xi.wang@gmail.com>
Cc: Haogang Chen <haogangchen@gmail.com>
Acked-by: default avatarRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      1ecd3c7e
  3. 08 Feb, 2012 6 commits
  5. 07 Feb, 2012 21 commits
GitLab Nexedi Edition | About GitLab | About Nexedi | 沪ICP备2021021310号-2 | 沪ICP备2021021310号-7