Import: robustness checks
Add more checks in the function graph code to detect errors and
perhaps print out better information if a bug happens.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: feature, let entry function decide to trace or not
This patch lets the graph tracer entry function decide if the tracing
should be done at the end as well. This requires all function graph
entry functions return 1 if it should trace, or 0 if the return should
not be traced.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: better dumpstack output
I noticed in my crash dumps and even in the stack tracer that a
lot of functions listed in the stack trace are simply
return_to_handler which is ftrace graphs way to insert its own
call into the return of a function.
But we lose out where the actually function was called from.
This patch adds in hooks to the dumpstack mechanism that detects
this and finds the real function to print. Both are printed to
let the user know that a hook is still in place.
This does give a funny side effect in the stack tracer output:
Depth Size Location (80 entries)
----- ---- --------
0) 4144 48 save_stack_trace+0x2f/0x4d
1) 4096 128 ftrace_call+0x5/0x2b
2) 3968 16 mempool_alloc_slab+0x16/0x18
3) 3952 384 return_to_handler+0x0/0x73
4) 3568 -240 stack_trace_call+0x11d/0x209
5) 3808 144 return_to_handler+0x0/0x73
6) 3664 -128 mempool_alloc+0x4d/0xfe
7) 3792 128 return_to_handler+0x0/0x73
8) 3664 -32 scsi_sg_alloc+0x48/0x4a [scsi_mod]
As you can see, the real functions are now negative. This is due
to them not being found inside the stack.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: clean up
Andrew Morton pointed out that the kernel convention of a variable
named page should be of type page struct. The ring buffer uses
a variable named "page" for a pointer to something else.
This patch converts those to be called "bpage" (as in "buffer page").
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: new ftrace_graph_stop function
While developing more features of function graph, I hit a bug that
caused the WARN_ON to trigger in the prepare_ftrace_return function.
Well, it was hard for me to find out that was happening because the
bug would not print, it would just cause a hard lockup or reboot.
The reason is that it is not safe to call printk from this function.
Looking further, I also found that it calls unregister_ftrace_graph,
which grabs a mutex and calls kstop machine. This would definitely
lock the box up if it were to trigger.
This patch adds a fast and safe ftrace_graph_stop() which will
stop the function tracer. Then it is safe to call the WARN ON.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: consistency change for function graph
This patch makes function graph record the mcount caller address
the same way the function tracer does.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: clean up
There exists macros for x86 asm to handle x86_64 and i386.
This patch updates function graph asm to use them.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: new API to ring buffer
This patch adds a new interface into the ring buffer that allows a
page to be read from the ring buffer on a given CPU. For every page
read, one must also be given to allow for a "swap" of the pages.
rpage = ring_buffer_alloc_read_page(buffer);
if (!rpage)
goto err;
ret = ring_buffer_read_page(buffer, &rpage, cpu, full);
if (!ret)
goto empty;
process_page(rpage);
ring_buffer_free_read_page(rpage);
The caller of these functions must handle any waits that are
needed to wait for new data. The ring_buffer_read_page will simply
return 0 if there is no data, or if "full" is set and the writer
is still on the current page.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: get ready for splice changes
This patch moves the commit and timestamp into the beginning of each
data page of the buffer. This change will allow the page to be moved
to another location (disk, network, etc) and still have information
in the page to be able to read it.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix for lockdep and ftrace
The raw_local_irq_save/restore confuses lockdep. This patch
converts them to the local_irq_save/restore variants.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Merge x86/dumpstack into tracing/ftrace because upcoming ftrace changes
depend on cleanups already in x86/dumpstack.
Also merge to latest upstream -rc.
On PowerPC 4xx or other non cache-coherent platforms, we lost the
appropriate cache flushing in dma_map_sg() when merging the 32 and
64-bit DMA code (commit 4fc665b88a,
"powerpc: Merge 32 and 64-bit dma code"). This restores it.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog:
[WATCHDOG] hpwdt: Fix kdump when using hpwdt
[WATCHDOG] hpwdt: set the mapped BIOS address space as executable
[WATCHDOG] iTCO_wdt: add PCI ID's for ICH9 & ICH10 chipsets
[WATCHDOG] iTCO_wdt : correct status clearing
[WATCHDOG] iTCO_wdt : problem with rebooting on new ICH9 based motherboards
[WATCHDOG] fix mtx1_wdt compilation failure
* 'linux-next' of git://git.infradead.org/ubifs-2.6:
UBIFS: pre-allocate bulk-read buffer
UBIFS: do not allocate too much
UBIFS: do not print scary memory allocation warnings
UBIFS: allow for gaps when dirtying the LPT
UBIFS: fix compilation warnings
MAINTAINERS: change UBI/UBIFS git tree URLs
UBIFS: endian handling fixes and annotations
UBIFS: remove printk
* 'kvm-updates/2.6.28' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm:
KVM: MMU: avoid creation of unreachable pages in the shadow
KVM: ppc: stop leaking host memory on VM exit
KVM: MMU: fix sync of ptes addressed at owner pagetable
KVM: ia64: Fix: Use correct calling convention for PAL_VPS_RESUME_HANDLER
KVM: ia64: Fix incorrect kbuild CFLAGS override
KVM: VMX: Fix interrupt loss during race with NMI
KVM: s390: Fix problem state handling in guest sigp handler
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
m68k: Update defconfigs for 2.6.28-rc7
macfb: Do not overflow fb_fix_screeninfo.id
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6:
[SCSI] stex: switch to block timeout
[SCSI] make scsi_eh_try_stu use block timeout
[SCSI] megaraid_sas: switch to block timeout
[SCSI] ibmvscsi: switch to block timeout
[SCSI] aacraid: switch to block timeout
[SCSI] zfcp: prevent double decrement on host_busy while being busy
[SCSI] zfcp: fix deadlock between wq triggered port scan and ERP
[SCSI] zfcp: eliminate race between validation and locking
[SCSI] zfcp: verify for correct rport state before scanning for SCSI devs
[SCSI] zfcp: returning an ERR_PTR where a NULL value is expected
[SCSI] zfcp: Fix opening of wka ports
[SCSI] zfcp: fix remote port status check
[SCSI] fc_transport: fix old bug on bitflag definitions
[SCSI] Fix hang in starved list processing
This fixes the MN10300 kernel module linking to match the toolchain. RELA
relocs don't use the value at the location being relocated. This has been
working because the tools always leave the value at the target location
cleared.
Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If xpc.ko and gru.ko are both statically linked into the kernel, then
xpc_init() can get called before gru_init() and make a call to one of the
gru's exported functions before the gru has initialized itself. The end
result is a NULL dereference.
Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In the CONFIG_SMP case the irq_choose_cpu() code was returning back
a logical cpu id not the physical id. We were writing that directly
into the HW register.
We need to be calling get_hard_smp_processor_id() so irq_choose_cpu()
always returns a physical cpu id.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Count the insertion of new pages in the statistics used to drive the
pageout scanning code. This should help the kernel quickly evict
streaming file IO.
We count on the fact that new file pages start on the inactive file LRU
and new anonymous pages start on the active anon list. This means
streaming file IO will increment the recent scanned file statistic, while
leaving the recent rotated file statistic alone, driving pageout scanning
to the file LRUs.
Pageout activity does its own list manipulation.
Signed-off-by: Rik van Riel <riel@redhat.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Tested-by: Gene Heskett <gene.heskett@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Devices which share the same queue, like floppies and mtd devices, get
registered multiple times in the bdi interface, but bdi accounts only the
last registered device of the devices sharing one queue.
On remove, all earlier registered devices leak, stay around in sysfs, and
cause "duplicate filename" errors if the devices are re-created.
This prevents the creation of multiple bdi interfaces per queue, and the
bdi device will carry the dev_t name of the block device which is the
first one registered, of the pool of devices using the same queue.
[akpm@linux-foundation.org: add a WARN_ON so we know which drivers are misbehaving]
Tested-by: Peter Korsgaard <jacmet@sunsite.dk>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The previous patch from Alan Cox ("nfsd: fix vm overcommit crash",
commit 731572d39f) fixed the problem where
knfsd crashes on exported shmemfs objects and strict overcommit is set.
But the patch forgot supporting the case when CONFIG_SECURITY is
disabled.
This patch copies a part of his fix which is mainly for detecting a bug
earlier.
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Junjiro R. Okajima <hooanon05@yahoo.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We guarantee 400ns delay at the time of issuing the command.
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Also while at it:
* Drop unused arguments from ide_complete_power_step().
* Move DEBUG_PM printk() from ide_end_drive_cmd() to
ide_complete_power_step().
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Respect current DMA setting during resume, otherwise PIO timings
may get destroyed if host uses shared PIO/MWDMA timings.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
It seems that on some nVidia controllers using AltStatus register
can be unreliable so default to Status register if the PCI device
is in Compatibility Mode. In order to achieve this:
* Add ide_pci_is_in_compatibility_mode() inline helper to <linux/ide.h>.
* Add IDE_HFLAG_BROKEN_ALTSTATUS host flag and set it in amd74xx host
driver for nVidia controllers in Compatibility Mode.
* Teach actual_try_to_identify() and drive_is_ready() about the new flag.
This fixes the regression caused by removal of CONFIG_IDEPCI_SHARE_IRQ
config option in 2.6.25 and using AltStatus register unconditionally when
available (kernel.org bugs #11659 and #10216).
[ Moreover for CONFIG_IDEPCI_SHARE_IRQ=y (which is what most people
and distributions use) it never worked correctly. ]
Thanks to Remy LABENE and Lars Winterfeld for help with debugging the problem.
More info at:
http://bugzilla.kernel.org/show_bug.cgi?id=11659http://bugzilla.kernel.org/show_bug.cgi?id=10216
Reported-by: Remy LABENE <remy.labene@free.fr>
Tested-by: Remy LABENE <remy.labene@free.fr>
Tested-by: Lars Winterfeld <lars.winterfeld@tu-ilmenau.de>
Acked-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Don't overflow the 16-character fb_fix_screeninfo id string (fixes some
console erasing and blanking artifacts). Have the ID default to "Unknown"
on machines with no built-in video and no nubus devices. Check for
fb_alloc_cmap failure.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Impact: extend and enable the function graph tracer to 64-bit x86
This patch implements the support for function graph tracer under x86-64.
Both static and dynamic tracing are supported.
This causes some small CPP conditional asm on arch/x86/kernel/ftrace.c I
wanted to use probe_kernel_read/write to make the return address
saving/patching code more generic but it causes tracing recursion.
That would be perhaps useful to implement a notrace version of these
function for other archs ports.
Note that arch/x86/process_64.c is not traced, as in X86-32. I first
thought __switch_to() was responsible of crashes during tracing because I
believed current task were changed inside but that's actually not the
case (actually yes, but not the "current" pointer).
So I will have to investigate to find the functions that harm here, to
enable tracing of the other functions inside (but there is no issue at
this time, while process_64.c stays out of -pg flags).
A little possible race condition is fixed inside this patch too. When the
tracer allocate a return stack dynamically, the current depth is not
initialized before but after. An interrupt could occur at this time and,
after seeing that the return stack is allocated, the tracer could try to
trace it with a random uninitialized depth. It's a prevention, even if I
hadn't problems with it.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tim Bird <tim.bird@am.sony.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix "no output from tracer" bug caused by ftrace_update_pid_func()
When disabling single thread function trace using
"echo -1 > set_ftrace_pid", the normal function trace
has to restore to original function, otherwise the normal
function trace will not work well.
Without this commit, something like below:
$ ps |grep 850
850 root 2556 S -/bin/sh
$ echo 850 > /debug/tracing/set_ftrace_pid
$ echo function > /debug/tracing/current_tracer
$ echo 1 > /debug/tracing/tracing_enabled
$ sleep 1
$ echo 0 > /debug/tracing/tracing_enabled
$ cat /debug/tracing/trace_pipe |wc -l
59704
$ echo -1 > /debug/tracing/set_ftrace_pid
$ echo 1 > /debug/tracing/tracing_enabled
$ sleep 1
$ echo 0 > /debug/tracing/tracing_enabled
$ more /debug/tracing/trace_pipe
<====== nothing output now!
it should output trace record.
Signed-off-by: Liming Wang <liming.wang@windriver.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (25 commits)
em28xx: remove backward compat macro added on a previous fix
V4L/DVB (9748): em28xx: fix compile warning
V4L/DVB (9743): em28xx: fix oops audio
V4L/DVB (9742): em28xx-alsa: implement another locking schema
V4L/DVB (9732): sms1xxx: use new firmware for Hauppauge WinTV MiniStick
V4L/DVB (9691): gspca: Move the video device to a separate area.
V4L/DVB (9690): gspca: Lock the subdrivers via module_get/put.
V4L/DVB (9689): gspca: Memory leak when disconnect while streaming.
V4L/DVB (9668): em28xx: fix a race condition with hald
V4L/DVB (9664): af9015: don't reconnect device in USB-bus
V4L/DVB (9647): em28xx: void having two concurrent control URB's
V4L/DVB (9646): em28xx: avoid allocating/dealocating memory on every control urb
V4L/DVB (9645): em28xx: Avoid memory leaks if registration fails
V4L/DVB (9639): Make dib0700 remote control support work with firmware v1.20
V4L/DVB (9635): v4l: s2255drv fix firmware test on big-endian
V4L/DVB (9634): Make sure the i2c gate is open before powering down tuner
V4L/DVB (9632): make em28xx aux audio input work
V4L/DVB (9631): Make s2api work for ATSC support
V4L/DVB (9627): em28xx: Avoid i2c register error for boards without eeprom
V4L/DVB (9608): Fix section mismatch warning for dm1105 during make
...
drivers/gpu/drm/i915/i915_irq.c: In function 'i915_disable_pipestat':
drivers/gpu/drm/i915/i915_irq.c:101: warning: control may reach end of non-void function 'i915_pipestat' being inlined
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix module removal bugs of i82875p_edac. Also i82975x_edac code seems to
have the same module removal bugs as in i82875p_edac.
The problems were:
1. In module removal i82875p_remove_one() is never called.
Variable i82875p_registered is newer changed from 1, which
guarantees i82875p_remove_one() is not called (and even if it were
called, it would be called in wrong order).
As a result, the edac_mc workque is not stopped and keeps probing.
If kernel debugging options are not enabled, user may not notice
anything going wrong.
if debugging options are enabled and I do "rmmod i82875p_edac", I
get:
edac debug: edac_pci_workq_function() checking
BUG: unable to handle kernel paging request at f882d16f
...
call trace:
[<f8834df3>] ? edac_mc_workq_function+0x55/0x7e [edac_core]
[<c0233974>] ? run_workqueue+0xd7/0x1a5
[<c023392f>] ? run_workqueue+0x92/0x1a5
[<f8834d9e>] ? edac_mc_workq_function+0x0/0x7e [edac_core]
[<c0233af9>] ? worker_thread+0xb7/0xc3
[<c0236a7b>] ? autoremove_wake_function+0x0/0x33
[<c0233a42>] ? worker_thread+0x0/0xc3
[<c0236809>] ? kthread+0x3b/0x61
[<c02367ce>] ? kthread+0x0/0x61
[<c0204587>] ? kernel_thread_helper+0x7/0x10
Fix for this is to get rid of needles variable i82875p_registered
altogether and run i82875p_remove_one() *before*
pci_unregister_driver().
2. edac_mc_del_mc() uses mci after freeing mci
edac_mc_del_mc() calls calls edac_remove_sysfs_mci_device(). The
kobject refcount of mci drops to 0 and mci is freed. After this
mci is accessed via debug print and i82875p_remove_one() still
uses mci->pvt and tries to free mci again with edac_mc_free().
The fix for this is add kobject_get(&mci->edac_mci_kobj) after
edac_mc_alloc(). Then the mci is still available after returning
from edac_mc_del_mc() with refcount 1, and mci->pvt is still
available. When i82875p_remove_one() finally calls edac_mc_free(),
this will cause kobject_put() and mci is released properly.
Signed-off-by: Jarkko Lavinen <jlavi@iki.fi>
Cc: Doug Thompson <norsk5@yahoo.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When I do "modprobe i82875p_edac" on my Asus P4C800 MB on kernels 2.6.26
or later, the module load fails due to BAR 0 collision. On 2.6.25 the
module loads just fine.
The overflow device on the MB seems to be hidden and its resources are not
allocated at normal PCI bus init. Log shows the missing resource problem:
EDAC DEBUG: i82875p_probe1()
PCI: 0000:00:06.0 reg 10 32bit mmio: [fecf0000, fecf0fff]
pci 0000:00:06.0: device not available because of BAR 0
[0xfecf0000-0xfecf0fff] collisions
EDAC i82875p: i82875p_setup_overfl_dev(): Failed to enable overflow
device
The patch below fixes this by calling pci_bus_assign_resources() after
the overflow device is revealed and added to the bus. With this patch
I am again able to load and use the module.
Signed-off-by: Jarkko Lavinen <jlavi@iki.fi>
Cc: Doug Thompson <norsk5@yahoo.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The commit aef7db4bd5 fixed the problem with
recursive locking in fb blanking code if blank is caused by user setting
the /sys/class/graphics/fb*/blank. However this broke the fbcon timeout
blanking.
If you use a driver that defines ->fb_blank operation and at the same time
that driver relies on other driver (e.g. backlight or lcd class) to blank
the screen, when the fbcon times out and tries to blank the fb, it will
call only fb driver blanker and won't notify the other driver. Thus FB
output is disabled, but the screen isn't blanked.
Restore fbcon blanking and at the same time apply the proper fix for the
above problem: if fbcon_blank is called with FBINFO_FLAG_USEREVENT, we are
already called through notification from fb_blank, thus we don't have to
blank the fb again.
Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel-doc handles macros now (it has for quite some time), so change the
ntfs_debug() macro's kernel-doc to be just before the macro instead of
before a phony function prototype.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Anton Altaparmakov <aia21@cantab.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The method for listing varargs in kernel-doc notation is:
* @...: these arguments are printed by the @fmt argument
but scripts/kernel-doc is confused: it always lists varargs as:
... variable arguments
and ignores the @...: line's description, but then prints that
line after the list of function parameters as though it's
not part of the function parameters.
This patch makes kernel-doc print the supplied @... description if it is
present; otherwise a boilerplate "variable arguments" is printed.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2nd part of the fixes needed for
http://bugzilla.kernel.org/show_bug.cgi?id=11796.
When the idr tree is either grown or shrunk, then the update to the number
of layers and the top pointer were not atomic. This race caused crashes.
The attached patch fixes that by replicating the layers counter in each
layer, thus idr_find doesn't need idp->layers anymore.
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Clement Calmels <cboulte@gmail.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- pci_map_sg/dma_map_sg are used with a scatter gather list that doesn't
come from the block layer (e.g. some network drivers do).
- how IOMMUs merge adjacent elements of the scatter/gather list is
independent of how the block layer determines sees elements.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
