Commit Graph

51127 Commits

Author SHA1 Message Date
Zwane Mwaikambo
a369a7100d [PATCH] x86: Don't probe for DDC on VBE1.2
VBE1.2 doesn't support function 15h (DDC) resulting in a 'hang' whilst
uncompressing kernel with some video cards. Make sure we check VBE version
before fiddling around with DDC.

http://bugzilla.kernel.org/show_bug.cgi?id=1458

Opened: 2003-10-30 09:12 Last update: 2007-02-13 22:03

Much thanks to Tobias Hain for help in testing and investigating the bug.
Tested on;

i386, Chips & Technologies 65548 VESA VBE 1.2
CONFIG_VIDEO_SELECT=Y
CONFIG_FIRMWARE_EDID=Y

Untested on x86_64.

Signed-off-by: Zwane Mwaikambo <zwane@infradead.org>
Signed-off-by: Andi Kleen <ak@suse.de>
2007-04-02 12:14:12 +02:00
Andi Kleen
0fb2ebfcb5 [PATCH] x86-64: Increase NMI watchdog probing timeout
A 4 core Opteron needs longer than 10 ticks for this.

Signed-off-by: Andi Kleen <ak@suse.de>
2007-04-02 12:14:12 +02:00
Andi Kleen
89e07569e4 [PATCH] x86-64: Let oprofile reserve MSR on all CPUs
The MSR reservation is per CPU and oprofile would only allocate them
on the CPU it was initialized on. Change this to handle all CPUs.

This also fixes a warning about unprotected use of smp_processor_id()
in preemptible kernels.

Signed-off-by: Andi Kleen <ak@suse.de>
2007-04-02 12:14:12 +02:00
Andi Kleen
3556ddfa92 [PATCH] x86-64: Disable local APIC timer use on AMD systems with C1E
AMD dual core laptops with C1E do not run the APIC timer correctly
when they go idle. Previously the code assumed this only happened
on C2 or deeper.  But not all of these systems report support C2.

Use a AMD supplied snippet to detect C1E being enabled and then disable
local apic timer use.

This supercedes an earlier workaround using DMI detection of specific systems.

Thanks to Mark Langsdorf for the detection snippet.

Signed-off-by: Andi Kleen <ak@suse.de>
2007-04-02 12:14:12 +02:00
Linus Torvalds
2e175a9004 Merge master.kernel.org:/home/rmk/linux-2.6-arm
* master.kernel.org:/home/rmk/linux-2.6-arm:
  [ARM] 4298/1: fix memory barriers for DMA coherent and SMP platforms
  [ARM] 4295/2: Fix error-handling in pxaficp_ir.c (version 2)
  [ARM] Fix __NR_kexec_load
  [ARM] Export dma_channel_active()
  [ARM] 4296/1: ixp4xx: compile fix
  [ARM] 4289/1: AT91: SAM9260 NAND flash timing
2007-04-01 14:43:57 -07:00
Lennert Buytenhek
398e692fd5 [ARM] 4298/1: fix memory barriers for DMA coherent and SMP platforms
This patch:
- Switches mb/rmb/wmb back to being full-blown DMBs on ARM SMP systems,
  since mb/rmb/wmb are required to order Normal memory accesses as well.
- Enables the use of DMB and ISB on XSC3 (which is an ARMv5TE ISA core
  but conforms to the ARMv6 memory ordering model and supports the
  various ARMv6 barriers.)
- Makes DMA coherent platforms (only ixp23xx at the moment) map
  mb/rmb/wmb to dmb(), as on DMA coherent platforms, DMA consistent
  mappings are done as Normal mappings, which are weakly ordered.

Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-04-01 22:38:36 +01:00
Guennadi Liakhovetski
9a4d93d49d [ARM] 4295/2: Fix error-handling in pxaficp_ir.c (version 2)
This patch addresses the following issues with the pxa2xx FIr driver:

1. increment overrun error counter and not frame error counter on ICSR1_ROR bit set in ICSR1.
2. drop frames reported with the frame error from the IC.
3. when resetting the receiver and preparing it for the next DMA in pxa_irda_fir_irq() actually clear the Rx FIFO. See description in Table 11-2 in PXA270 Developer's Manual of the RXE bit.

Correction added in version 2: clearing the IC Rx FIFO also has to be done in pxa_irda_fir_dma_tx_irq()

Signed-off-by: G. Liakhovetski <gl@dsa-ac.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-04-01 22:38:01 +01:00
Russell King
6c330ba72c [ARM] Fix __NR_kexec_load
It's __NR_kexec_load, not __NR_sys_kexec_load

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-04-01 22:35:01 +01:00
Jan Beulich
c21b1e4d9b [PATCH] kbuild: fix dependency generation
Commit 2e3646e51b changed the way the
split config tree is built, but failed to also adjust fixdep accordingly
- if changing a config option from or to m, files referencing the
respective CONFIG_..._MODULE (but not the corresponding CONFIG_...)
didn't get rebuilt.

The problem is that trisate symbol are represent with three different
symbols:
    SYMBOL=n => no symbol defined
    SYMBOL=y => CONFIG_SYMBOL defined to '1'
    SYMBOL=m => CONFIG_SYMBOL_MODULE defined to '1'

But conf_split_config do not distingush between the =y and =m case, so
only the =y case is honoured.

This is fixed in fixdep so when a CONFIG symbol with _MODULE is found we
skip that part and only look for the CONFIG_SYMBOL version.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-04-01 14:23:57 -07:00
Linus Torvalds
f5ef2abcbe driver core: do not wait unnecessarily in driver_unregister()
Ingo reported that built-in drivers suffered bootup hangs with certain
driver unregistry sequences, due to sysfs breakage.

Do the minimal fix for v2.6.21: only wait if the driver is a module.

Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-04-01 10:54:13 -07:00
Russell King
ec14d7964b [ARM] Export dma_channel_active()
dma_channel_active() is used by some modules and is part of our
DMA API, so export it.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-03-31 21:36:53 +01:00
Linus Torvalds
755948cfca Merge master.kernel.org:/pub/scm/linux/kernel/git/herbert/crypto-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  [CRYPTO] api: Flush the current page right than the next
  [CRYPTO] api: Use the right value when advancing scatterwalk_copychunks
2007-03-30 20:40:56 -07:00
Herbert Xu
9f11672728 [CRYPTO] api: Flush the current page right than the next
On platforms where flush_dcache_page is needed we're currently flushing
the next page right than the one we've just processed.  This patch fixes
the off-by-one error.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-03-31 12:58:20 +10:00
Herbert Xu
beff804d8d [PATCH] crypto api: Use the right value when advancing scatterwalk_copychunks
In the scatterwalk_copychunks loop, We should be advancing by
len_this_page and not nbytes.  The latter is the total length.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-30 19:26:33 -07:00
Paolo 'Blaisorblade' Giarrusso
c35e584c08 [PATCH] uml: fix static linking for real
There was a typo in commit 7632fc8f80,
preventing it from working - 32bit binaries crashed hopelessly before
the below fix and work perfectly now.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-30 19:21:30 -07:00
Herbert Xu
4ee531a3e6 [CRYPTO] api: Use the right value when advancing scatterwalk_copychunks
In the scatterwalk_copychunks loop, We should be advancing by
len_this_page and not nbytes.  The latter is the total length.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-03-31 12:16:20 +10:00
Linus Torvalds
a5bd1786fb Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6:
  Revert "ACPI: parse 2nd MADT by default"
2007-03-30 11:49:37 -07:00
Len Brown
4e381a4f06 Revert "ACPI: parse 2nd MADT by default"
This reverts commit 09fe58356d.
http://bugzilla.kernel.org/show_bug.cgi?id=8283

Signed-off-by: Len Brown <len.brown@intel.com>
2007-03-30 14:16:10 -04:00
Jens Axboe
964429252a [PATCH] Maxtor 6B250S0/BANC1B70 hangs with NCQ
I've seen this several times on this drive, completely reproducible.

Once it has hung, power needs to be cut from the drive to recover it, a
simple reboot is not enough.  So I'd suggest disabling NCQ on this
drive.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Acked-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-30 11:13:06 -07:00
Vladimir Barinov
6b8777b468 [ARM] 4296/1: ixp4xx: compile fix
Fix compilation fail for ixp4xx platforms for the case when CONFIG_IXP4XX_INDIRECT_PCI is set. That is due to the check_signature() is appeared in include/linux/io.h.

Signed-off-by: Vladimir Barinov <vbarinov@ru.mvista.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2007-03-30 16:56:05 +01:00
Linus Torvalds
ce20269d1e Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
  [MIPS] SMTC: Fix recursion in instant IPI replay code.
  [MIPS] BCM1480: Fix setting of irq affinity.
  [MIPS] do_page_fault() needs to use raw_smp_processor_id().
  [MIPS] SMTC: Fix false trigger of debug code on single VPE.
  [MIPS] SMTC: irq_{enter,leave} and kstats keeping for relayed timer ints.
  [MIPS] lockdep: Deal with interrupt disable hazard in TRACE_IRQFLAGS
  [MIPS] lockdep: Handle interrupts in R3000 style c0_status register.
  [MIPS] MV64340: Add missing prototype for mv64340_irq_init().
  [MIPS] MT: MIPS_MT_SMTC_INSTANT_REPLAY currently conflicts with PREEMPT.
  [MIPS] EV64120: Include <asm/irq.h> to fix warning.
  [MIPS] Ocelot: Fix warning.
  [MIPS] Ocelot: Give PMON_v1_setup a proper prototype.
2007-03-29 20:30:12 -07:00
Linus Torvalds
9754c5f6cb Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6:
  [IA64] Fix arch/ia64/pci/pci.c:571: warning: `return' with a value
  [IA64] Speed up boot - skip unnecessary clock calibration
  [IA64] bugfix stack layout upside-down
  [IA64] Fix possible invalid memory access in ia64_setup_msi_irq()
2007-03-29 20:25:03 -07:00
Ralf Baechle
8a1e97ee2e [MIPS] SMTC: Fix recursion in instant IPI replay code.
local_irq_restore -> raw_local_irq_restore -> irq_restore_epilog ->
	smtc_ipi_replay -> smtc_ipi_dq -> spin_unlock_irqrestore ->
	_spin_unlock_irqrestore -> local_irq_restore

The recursion does abort when there is no more IPI queued for a CPU, so
this isn't usually fatal which is why we got away with this for so long
until this was discovered by code inspection.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-03-29 23:46:36 +01:00
Mark Mason
6c9fde4bff [MIPS] BCM1480: Fix setting of irq affinity.
Signed-off-by: Mark Mason <mason@broadcom.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-03-29 23:46:36 +01:00
Ralf Baechle
d6f703602f [MIPS] do_page_fault() needs to use raw_smp_processor_id().
Original patch posted by Deepak Saxena <dsaxena@plexity.net>.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-03-29 23:46:36 +01:00
Ralf Baechle
20bb25d10f [MIPS] SMTC: Fix false trigger of debug code on single VPE.
Make smtc_setup_irq() update the list of interrupts which need to be
watched by the debug code itself.  Also there is no need to initialize the
IPI swint when running with a single VPE, so don't initialize it.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-03-29 23:46:36 +01:00
Ralf Baechle
ae036b7908 [MIPS] SMTC: irq_{enter,leave} and kstats keeping for relayed timer ints.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-03-29 23:46:35 +01:00
Chris Dearman
fe99f1b184 [MIPS] lockdep: Deal with interrupt disable hazard in TRACE_IRQFLAGS
Between the mtc0 or di instruction that disables interrupts and the
following hazard barrier a processor may still take interrupts.  If an
interrupt is taken after interrupts are disabled but before the state
is updated it will appear to restore_all that it is incorrectly returning
with interrupts disabled.

Signed-off-by: Chris Dearman <chris@mips.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-03-29 23:46:35 +01:00
Chris Dearman
cbde5ebc97 [MIPS] lockdep: Handle interrupts in R3000 style c0_status register.
Check the IEP bit for R3000 style processors when checking to see if
interrupts will be reenabled in restore_all.

Signed-off-by: Chris Dearman <chris@mips.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-03-29 23:46:35 +01:00
Ralf Baechle
eb541cb240 [MIPS] MV64340: Add missing prototype for mv64340_irq_init().
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-03-29 23:46:35 +01:00
Ralf Baechle
619af723ac [MIPS] MT: MIPS_MT_SMTC_INSTANT_REPLAY currently conflicts with PREEMPT.
So until MIPS_MT_SMTC_INSTANT_REPLAY has been rewritten to solve this
issue, don't allow selecting it with PREEMPT.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-03-29 23:46:35 +01:00
Ralf Baechle
af2944ac54 [MIPS] EV64120: Include <asm/irq.h> to fix warning.
arch/mips/pci/pci-ev64120.c:10: warning: implicit declaration of function 'allocate_irqno'

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-03-29 23:46:35 +01:00
Ralf Baechle
9486d594ba [MIPS] Ocelot: Fix warning.
Remove unused variable.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-03-29 23:46:35 +01:00
Ralf Baechle
448f283c11 [MIPS] Ocelot: Give PMON_v1_setup a proper prototype.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-03-29 23:46:34 +01:00
Tony Luck
dbfc2f6f95 [IA64] Fix arch/ia64/pci/pci.c:571: warning: `return' with a value
Typo/thinko in bba6f6fc68

Signed-off-by: Tony Luck <tony.luck@intel.com>
2007-03-29 15:41:37 -07:00
Jack Steiner
ead6caae1e [IA64] Speed up boot - skip unnecessary clock calibration
Skip clock calibration if cpu being brought online is exactly the same
speed, stepping, etc., as the previous cpu. This significantly reduces
the time to boot very large systems.

Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2007-03-29 15:17:11 -07:00
KAMEZAWA Hiroyuki
83d2cd3de4 [IA64] bugfix stack layout upside-down
ia64 expects following vm layout:

== low memory
[register-stack grows up]
[memory-stack grows down]
== high memory

But the code assigns the base of the register stack at the
maximum stack size offset from the fixed address where the
stack *might* start.  Stack randomization will result in the
memory stack starting at a lower address than this, and if the
user has set a low stack limit with "ulimit -s", then you can
end up with the register stack above the memory stack (or if
you were very unlucky right on top of it!).

Fix: Calculate the base address for the register stack starting
from the actual address of the memory stack.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2007-03-29 15:15:24 -07:00
Kenji Kaneshige
8a3a0ee736 [IA64] Fix possible invalid memory access in ia64_setup_msi_irq()
The following 'if' statement in ia64_setup_msi_irq() always fails even
if create_irq() returns <0 value, because variable 'irq' is defined as
unsigned int. It would cause invalid memory access.

        irq = create_irq();
        if (irq < 0)
                return irq;

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2007-03-29 15:02:58 -07:00
Linus Torvalds
efab03d998 Merge branch 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/netdev-2.6
* 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/netdev-2.6:
  NetXen: Fix hardware access for ppc architecture.
  sis190: new PHY support
  atl1: save mac address on remove
2007-03-29 13:22:07 -07:00
Linus Torvalds
9415fddd99 Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6:
  [IFB]: Fix crash on input device removal
  [BNX2]: Fix link interrupt problem.
2007-03-29 13:15:13 -07:00
Timur Tabi
297640e89e [POWERPC] qe: ucc_slow.guemr is in the wrong place
The definition of struct ucc_slow puts the guemr register immediately after the
utpt register, when it should be at offset 0x90.  This patch adds the missing
0x52-byte padding.

Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2007-03-29 14:33:56 -05:00
Chuck Meade
7f013bc9d0 [POWERPC] qe: Fix QUICC Engine SDMA setup errors
Correct the alignment of the internal buffer used by the QUICC Engine
SDMA controller to 4Kbytes.  Correct the shift direction in the logic
that sets up the SDMR register for the QUICC Engine SDMA controller.

Signed-off-by: Chuck Meade <chuckmeade@mindspring.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2007-03-29 14:33:42 -05:00
Patrick McHardy
c01003c205 [IFB]: Fix crash on input device removal
The input_device pointer is not refcounted, which means the device may
disappear while packets are queued, causing a crash when ifb passes packets
with a stale skb->dev pointer to netif_rx().

Fix by storing the interface index instead and do a lookup where neccessary.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Acked-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-03-29 11:46:52 -07:00
Maxim Levitsky
399afa4fc9 [PATCH] Add suspend/resume for HPET
This adds support of suspend/resume on i386 for HPET, which fixes a
number of timer-related failures around STR.

Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Acked-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Acked-by: Jeff Chua <jeff.chua.linux@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-29 10:25:32 -07:00
Linus Torvalds
22c8c65d24 Merge branch 'for-linus' of git://git.kernel.dk/data/git/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/data/git/linux-2.6-block:
  [PATCH] splice: partial write fix
2007-03-29 08:23:52 -07:00
Carsten Otte
a76c0b9763 [PATCH] mm: fix xip issue with /dev/zero
Fix the bug, that reading into xip mapping from /dev/zero fills the user
page table with ZERO_PAGE() entries.  Later on, xip cannot tell which pages
have been ZERO_PAGE() filled by access to a sparse mapping, and which ones
origin from /dev/zero.  It will unmap ZERO_PAGE from all mappings when
filling the sparse hole with data.  xip does now use its own zeroed page
for its sparse mappings.  Please apply.

Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-29 08:22:26 -07:00
Hugh Dickins
90ed52ebe4 [PATCH] holepunch: fix mmap_sem i_mutex deadlock
sys_madvise has down_write of mmap_sem, then madvise_remove calls
vmtruncate_range which takes i_mutex and i_alloc_sem: no, we can easily devise
deadlocks from that ordering.

madvise_remove drop mmap_sem while calling vmtruncate_range: luckily, since
madvise_remove doesn't split or merge vmas, it's easy to handle this case with
a NULL prev, without restructuring sys_madvise.  (Though sad to retake
mmap_sem when it's unlikely to be needed, and certainly down_read is
sufficient for MADV_REMOVE, unlike the other madvices.)

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Miklos Szeredi <mszeredi@suse.cz>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-29 08:22:26 -07:00
Hugh Dickins
16a100190d [PATCH] holepunch: fix disconnected pages after second truncate
shmem_truncate_range has its own truncate_inode_pages_range, to free any pages
racily instantiated while it was in progress: a SHMEM_PAGEIN flag is set when
this might have happened.  But holepunching gets no chance to clear that flag
at the start of vmtruncate_range, so it's always set (unless a truncate came
just before), so holepunch almost always does this second
truncate_inode_pages_range.

shmem holepunch has unlikely swap<->file races hereabouts whatever we do
(without a fuller rework than is fit for this release): I was going to skip
the second truncate in the punch_hole case, but Miklos points out that would
make holepunch correctness more vulnerable to swapoff.  So keep the second
truncate, but follow it by an unmap_mapping_range to eliminate the
disconnected pages (freed from pagecache while still mapped in userspace) that
it might have left behind.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Miklos Szeredi <mszeredi@suse.cz>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-29 08:22:25 -07:00
Hugh Dickins
1ae7000630 [PATCH] holepunch: fix shmem_truncate_range punch locking
Miklos Szeredi observes that during truncation of shmem page directories,
info->lock is released to improve latency (after lowering i_size and
next_index to exclude races); but this is quite wrong for holepunching, which
receives no such protection from i_size or next_index, and is left vulnerable
to races with shmem_unuse, shmem_getpage and shmem_writepage.

Hold info->lock throughout when holepunching?  No, any user could prevent
rescheduling for far too long.  Instead take info->lock just when needed: in
shmem_free_swp when removing the swap entries, and whenever removing a
directory page from the level above.  But so long as we remove before
scanning, we can safely skip taking the lock at the lower levels, except at
misaligned start and end of the hole.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Miklos Szeredi <mszeredi@suse.cz>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-29 08:22:25 -07:00
Hugh Dickins
a2646d1e6c [PATCH] holepunch: fix shmem_truncate_range punching too far
Miklos Szeredi observes BUG_ON(!entry) in shmem_writepage() triggered in rare
circumstances, because shmem_truncate_range() erroneously removes partially
truncated directory pages at the end of the range: later reclaim on pages
pointing to these removed directories triggers the BUG.  Indeed, and it can
also cause data loss beyond the hole.

Fix this as in the patch proposed by Miklos, but distinguish between "limit"
(how far we need to search: ignore truncation's next_index optimization in the
holepunch case - if there are races it's more consistent to act on the whole
range specified) and "upper_limit" (how far we can free directory pages:
generally we must be careful to keep partially punched pages, but can relax at
end of file - i_size being held stable by i_mutex).

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Miklos Szeredi <mszeredi@suse.cs>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-29 08:22:25 -07:00