Handle the misconfiguration where CONFIG_PHYSICAL_START is
incompatible with CONFIG_PHYSICAL_ALIGN. This is a configuration
error, but one which arises easily since Kconfig doesn't have the
smarts to express the true relationship between these two variables.
Hence, align __PHYSICAL_START the same way we align LOAD_PHYSICAL_ADDR
in <asm/boot.h>.
For non-relocatable kernels, this would cause the boot to fail.
[ Impact: fix boot failures for non-relocatable kernels ]
Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
H. Peter Anvin [Tue, 12 May 2009 18:33:08 +0000 (11:33 -0700)]
x86, boot: correct sanity checks in boot/compressed/misc.c
arch/x86/boot/compressed/misc.c contains several sanity checks on the
output address. Correct constraints that are no longer correct:
- the alignment test should be MIN_KERNEL_ALIGN on both 32 and 64
bits.
- the 64 bit maximum address was set to 2^40, which was the limit of
one specific x86-64 implementation. Change the test to 2^46, the
current Linux limit, and at least try to test the end rather than
the beginning.
- for non-relocatable kernels, test against LOAD_PHYSICAL_ADDR on both
32 and 64 bits.
[ Impact: fix potential boot failure due to invalid tests ]
H. Peter Anvin [Thu, 7 May 2009 23:54:11 +0000 (16:54 -0700)]
x86: add extension fields for bootloader type and version
A long ago, in days of yore, it all began with a god named Thor.
There were vikings and boats and some plans for a Linux kernel
header. Unfortunately, a single 8-bit field was used for bootloader
type and version. This has generally worked without *too* much pain,
but we're getting close to flat running out of ID fields.
Add extension fields for both type and version. The type will be
extended if it the old field is 0xE; the version is a simple MSB
extension.
Keep /proc/sys/kernel/bootloader_type containing
(type << 4) + (ver & 0xf) for backwards compatiblity, but also add
/proc/sys/kernel/bootloader_version which contains the full version
number.
[ Impact: new feature to support more bootloaders ]
H. Peter Anvin [Thu, 7 May 2009 21:19:34 +0000 (14:19 -0700)]
x86: make CONFIG_RELOCATABLE the default
Remove the EXPERIMENTAL tag from CONFIG_RELOCATABLE and make it the
default. Relocatable kernels have been used for a while now, and
should now have identical semantics to non-relocatable kernels when
loaded by a non-relocating bootloader.
H. Peter Anvin [Mon, 11 May 2009 23:12:16 +0000 (16:12 -0700)]
x86: default CONFIG_PHYSICAL_START and CONFIG_PHYSICAL_ALIGN to 16 MB
Default CONFIG_PHYSICAL_START and CONFIG_PHYSICAL_ALIGN each to 16 MB,
so that both non-relocatable and relocatable kernels are loaded at
16 MB by a non-relocating bootloader. This is somewhat hacky, but it
appears to be the only way to do this that does not break some some
set of existing bootloaders.
We want to avoid the bottom 16 MB because of large page breakup,
memory holes, and ZONE_DMA. Embedded systems may need to reduce this,
or update their bootloaders to be aware of the new min_alignment field.
[ Impact: performance improvement, avoids problems on some systems ]
H. Peter Anvin [Mon, 11 May 2009 22:56:08 +0000 (15:56 -0700)]
x86, boot: make kernel_alignment adjustable; new bzImage fields
Make the kernel_alignment field adjustable; this allows us to set it
to a large value (intended to be 16 MB to avoid ZONE_DMA contention,
memory holes and other weirdness) while a smart bootloader can still
force a loading at a lesser alignment if absolutely necessary.
Also export pref_address (preferred loading address, corresponding to
the link-time address) and init_size, the total amount of linear
memory the kernel will require during initialization.
[ Impact: allows better kernel placement, gives bootloader more info ]
H. Peter Anvin [Sat, 9 May 2009 00:42:16 +0000 (17:42 -0700)]
x86, boot: determine compressed code offset at compile time
Determine the compressed code offset (from the kernel runtime address)
at compile time. This allows some minor optimizations in
arch/x86/boot/compressed/head_*.S, but more importantly it makes this
value available to the build process, which will enable a future patch
to export the necessary linear memory footprint into the bzImage
header.
H. Peter Anvin [Fri, 8 May 2009 23:45:15 +0000 (16:45 -0700)]
x86, boot: use appropriate rep string for move and clear
In the pre-decompression code, use the appropriate largest possible
rep movs and rep stos to move code and clear bss, respectively. For
reverse copy, do note that the initial values are supposed to be the
address of the first (highest) copy datum, not one byte beyond the end
of the buffer.
rep strings are not necessarily the fastest way to perform these
operations on all current processors, but are likely to be in the
future, and perhaps more importantly, we want to encourage the
architecturally right thing to do here.
This also fixes a couple of trivial inefficiencies on 64 bits.
H. Peter Anvin [Fri, 8 May 2009 23:27:41 +0000 (16:27 -0700)]
x86, boot: set up the decompression stack as early as possible
Set up the decompression stack as soon as we know where it needs to
go. That way we have a full-service stack as soon as possible, rather
than relying on the BP_scratch field.
Note that the stack does need to be empty during bss zeroing (or
else the stack needs to be moved out of the bss segment, which is also
an option.)
H. Peter Anvin [Fri, 8 May 2009 23:20:34 +0000 (16:20 -0700)]
x86, boot: straighten out ranges to copy/zero in compressed/head*.S
Both on 32 and 64 bits, we copy all the way up to the end of bss,
except that on 64 bits there is a hack to avoid copying on top of the
page tables. There is no point in copying bss at all, especially
since we are just about to zero it all anyway.
To clean up and unify the handling, we now do:
- copy from startup_32 to _bss.
- zero from _bss to _ebss.
- the _ebss symbol is aligned to an 8-byte boundary.
- the page tables are moved to a separate section.
Use _bss as the copy endpoint since _edata may be misaligned.
H. Peter Anvin [Fri, 8 May 2009 22:59:13 +0000 (15:59 -0700)]
x86, boot: stylistic cleanups for boot/compressed/head_64.S
Clean up style issues in arch/x86/boot/compressed/head_64.S. This
file had a lot fewer style issues than its 32-bit cousin, but the ones
it has are worth fixing, especially since it makes the two files more
similar.
Simplify the arch/x86/boot/compressed/Makefile, by using the new
capability of specifying multiple inputs to a compressor, and the
CONFIG_X86_NEED_RELOCS Kconfig symbol.
Signed-off-by: H. Peter Anvin <hpa@zytor.com> Acked-by: Sam Ravnborg <sam@ravnborg.org>
H. Peter Anvin [Wed, 6 May 2009 04:20:51 +0000 (21:20 -0700)]
x86: add a Kconfig symbol for when relocations are needed
We only need to build relocations when we are building a 32-bit
relocatable kernel. Rather than unnecessarily complicating the
Makefiles, make an explicit Kbuild symbol for this.
[ Impact: permits future cleanup ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: Sam Ravnborg <sam@ravnborg.org>
H. Peter Anvin [Wed, 6 May 2009 04:17:15 +0000 (21:17 -0700)]
kbuild: allow compressors (gzip, bzip2, lzma) to take multiple inputs
Allow the compression commands in Kbuild (i.e. gzip, bzip2, lzma) to
take multiple input files and emit the concatenated compressed
output. This avoids an intermediate step when a kernel image is built
from multiple components, such as the relocatable x86-32 kernel.
Sam Ravnborg integrated the bin_size script into the Makefile.
[ Impact: new build feature, not yet used ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com> Acked-by: Sam Ravnborg <sam@ravnborg.org>
H. Peter Anvin [Fri, 1 May 2009 00:59:36 +0000 (17:59 -0700)]
x86, boot: align the .bss section in the decompressor
Aligning the .bss section makes it trivial to use large operation
sizes for moving the initialized sections and clearing the .bss.
The alignment chosen (L1 cache) is somewhat arbitrary, but should be
large enough to avoid all known performance traps and small enough to
not cause troubles.
__init_begin/_end symbols should be inside sections as well,
otherwise the relocatable kernel gets confused when freeing
init sections in the wrong place.
[ Impact: fix bootup crash ]
Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Tim Abbott <tabbott@MIT.EDU> Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <20090429105056.GA28720@uranus.ravnborg.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Sam Ravnborg [Wed, 29 Apr 2009 07:47:25 +0000 (09:47 +0200)]
x86, vmlinux.lds: unify first part of initdata
32-bit:
- Move definition of __init_begin outside output_section
because it covers more than one section
- Move ALIGN() for end-of-section inside .smp_locks output section.
Same effect but the intent is better documented that
we need both start and end aligned.
Sam Ravnborg [Wed, 29 Apr 2009 07:47:23 +0000 (09:47 +0200)]
x86, vmlinux.lds: unify data output sections
For 64 bit the following functional changes are introduced:
- .data.page_aligned has moved
- .data.cacheline_aligned has moved
- .data.read_mostly has moved
- ALIGN() moved out of output section for .data.cacheline_aligned
- ALIGN() moved out of output section for .data.page_aligned
Notice that 32 bit and 64 bit has different location of _edata.
.data_nosave is 32 bit only as 64 bit is special due to PERCPU.
[ Impact: 32-bit: cleanup, 64-bit: use 32-bit linker script ]
Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Tim Abbott <tabbott@MIT.EDU> Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <1240991249-27117-7-git-send-email-sam@ravnborg.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Sam Ravnborg [Wed, 29 Apr 2009 07:47:21 +0000 (09:47 +0200)]
x86, vmlinux.lds: unify .text output sections
32 bit x86 had a dedicated .text.head output section,
whereas 64 bit had it all in a single output section.
In the unified version the dedicated .text.head output section
was kept to have full control over the head code.
32 bit:
- Moved definition of _stext to the linker script.
The definition is located _after_ .text.page_aligned as this
is what 32 bit did before.
The ALIGN(8) was introduced so we hit the exact same address
(on the tested config) before and after the move.
I assume that it is a bug that _stext did not cover the
.text.page_aligned section - if this is true it can be fixed
in a follow-up patch (and the ugly ALIGN() can be dropped).
[ Impact: 64-bit: cleanup, 32-bit: use the 64-bit linker script ]
Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Tim Abbott <tabbott@MIT.EDU> Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <1240991249-27117-5-git-send-email-sam@ravnborg.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
output and realize that they're basially exactly the same except for
trivial naming differences, and the fact that the 64-bit version has a
"pgtable" thing.
So unify them.
There's some trivial cleanup there (make the output format a Kconfig thing
rather than doing #ifdef's for it, and unify both 32-bit and 64-bit BSS
end to "_ebss", where 32-bit used to use the traditional "_end"), but
other than that it's really very mindless and straigt conversion.
For example, I think we should aim to remove "startup_32" vs "startup_64",
and just call it "startup", and get rid of one more difference. I didn't
do that.
Also, notice the comment in the unified vmlinux.lds.S talks about
"head_64" and "startup_32" which is an odd and incorrect mix, but that was
actually what the old 64-bit only lds file had, so the confusion isn't
new, and now that mixing is arguably more accurate thanks to the
vmlinux.lds.S file being shared between the two cases ;)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
ALSA: hda - Fix the cmd cache keys for amp verbs
ALSA: add missing definitions(letters) to HD-Audio.txt
ALSA: hda - Add quirk mask for Fujitsu Amilo laptops with ALC883
[ALSA] intel8x0: add one retry to the ac97_clock measurement routine
[ALSA] intel8x0: fix wrong conditions in ac97_clock measure routine
ALSA: hda - Avoid call of snd_jack_report at release
ALSA: add private_data to struct snd_jack
ALSA: snd-usb-caiaq: rename files to remove redundant information in file pathes
ALSA: snd-usb-caiaq: clean up header includes
ALSA: sound/pci: use memdup_user()
ALSA: sound/usb: use memdup_user()
ALSA: sound/isa: use memdup_user()
ALSA: sound/core: use memdup_user()
[ALSA] intel8x0: do not use zero value from PICB register
[ALSA] intel8x0: an attempt to make ac97_clock measurement more reliable
[ALSA] pcm-midlevel: Add more strict buffer position checks based on jiffies
[ALSA] hda_intel: fix unexpected ring buffer positions
ASoC: Disable S3C64xx support in Kconfig
ASoC: magician: remove un-necessary #include of pxa-regs.h and hardware.h
Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block: (28 commits)
cfq-iosched: add close cooperator code
cfq-iosched: log responsible 'cfqq' in idle timer arm
cfq-iosched: tweak kick logic a bit more
cfq-iosched: no need to save interrupts in cfq_kick_queue()
brd: fix cacheflushing
brd: support barriers
swap: Remove code handling bio_alloc failure with __GFP_WAIT
gfs2: Remove code handling bio_alloc failure with __GFP_WAIT
ext4: Remove code handling bio_alloc failure with __GFP_WAIT
dio: Remove code handling bio_alloc failure with __GFP_WAIT
block: Remove code handling bio_alloc failure with __GFP_WAIT
bio: add documentation to bio_alloc()
splice: add helpers for locking pipe inode
splice: remove generic_file_splice_write_nolock()
ocfs2: fix i_mutex locking in ocfs2_splice_to_file()
splice: fix i_mutex locking in generic_splice_write()
splice: remove i_mutex locking in splice_from_pipe()
splice: split up __splice_from_pipe()
block: fix SG_IO to return a proper error value
cfq-iosched: don't delay queue kick for a merged request
...
Fix the key value generation for get/set amp verbs. The upper bits of
the parameter have to be combined with the verb value to be unique for
each direction/index of amp access.
This fixes the resume problem on some hardwares like Macbook after
the channel mode is changed.
Tested-by: Johannes Berg <johannes@sipsolutions.net> Cc: <stable@kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
powerpc: pseries/dtl.c should include asm/firmware.h
powerpc: Fix data-corrupting bug in __futex_atomic_op
powerpc/pseries: Set error_state to pci_channel_io_normal in eeh_report_reset()
powerpc: Allow 256kB pages with SHMEM
powerpc: Document new FSL I2C bindings and cleanup
powerpc/mm: Fix compile warning
powerpc/85xx: TQM8548: update defconfig
powerpc/85xx: TQM8548: use proper phy-handles for enet2 and enet3
powerpc/85xx: TQM85xx: correct address of LM75 I2C device nodes
powerpc: Add support for early tlbilx opcode
powerpc: Fix tlbilx opcode
It turns out that 'smp_call_function_many()' doesn't work at all like
'smp_call_function_single()', and my change to Andrew's patch to use it
rather than a loop over all CPU's acpi-cpufreq doesn't work.
My bad.
'smp_call_function_many()' has two "features" (aka "documented bugs"):
(a) it needs to be called with preemption disabled, because it uses
smp_processor_id() without guarding the CPU lookup with 'get_cpu()'
and 'put_cpu()' like the 'single' variant does.
(b) even if the current CPU is part of the CPU mask, it won't do the
call on that CPU.
Still, we're better off trying to use 'smp_call_function_many()' than
looping over CPU's, since it at least in theory allows us to use a
broadcast IPI and do it all in parallel. So let's just work around the
silly semantic bugs in that function.
Reported-and-tested-by: Ali Gholami Rudi <ali@rudi.ir> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@linux-foundation.org>, Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Dave Jones <davej@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If we have processes that are working in close proximity to each
other on disk, we don't want to idle wait. Instead allow the close
process to issue a request, getting better aggregate bandwidth.
The anticipatory scheduler has similar checks, noop and deadline do
not need it since they don't care about process <-> io mappings.
The code for CFQ is a little more involved though, since we split
request queues into per-process contexts.
This fixes a performance problem with eg dump(8), since it uses
several processes in some silly attempt to speed IO up. Even if
dump(8) isn't really a valid case (it should be fixed by using
CLONE_IO), there are other cases where we see close processes
and where idling ends up hurting performance.
Credit goes to Jeff Moyer <jmoyer@redhat.com> for writing the
initial implementation.
We only kick the dispatch for an idling queue, if we think it's a
(somewhat) fully merged request. Also allow a kick if we have other
busy queues in the system, since we don't want to risk waiting for
a potential merge in that case. It's better to get some work done and
proceed.
Nick Piggin [Wed, 15 Apr 2009 08:32:07 +0000 (10:32 +0200)]
brd: fix cacheflushing
brd is missing a flush_dcache_page. On 2nd thoughts, perhaps it is the
pagecache's responsibility to flush user virtual aliases (the driver of
course should flush kernel virtual mappings)... but anyway, there
already exists cache flushing for one direction of transfer, so we
should add the other.
Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Nick Piggin [Wed, 15 Apr 2009 08:27:07 +0000 (10:27 +0200)]
brd: support barriers
brd is always ordered (not that it matters, as it is defined not to
survive when the system goes down). So tell the block layer it is
ordered, which might be of help with testing filesystems.
Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
There are lots of sequences like this, especially in splice code:
if (pipe->inode)
mutex_lock(&pipe->inode->i_mutex);
/* do something */
if (pipe->inode)
mutex_unlock(&pipe->inode->i_mutex);
so introduce helpers which do the conditional locking and unlocking.
Also replace the inode_double_lock() call with a pipe_double_lock()
helper to avoid spreading the use of this functionality beyond the
pipe code.
This patch is just a cleanup, and should cause no behavioral changes.
Remove the now unused generic_file_splice_write_nolock() function.
It's conceptually broken anyway, because splice may need to wait for
pipe events so holding locks across the whole operation is wrong.
ocfs2: fix i_mutex locking in ocfs2_splice_to_file()
Rearrange locking of i_mutex on destination and call to
ocfs2_rw_lock() so locks are only held while buffers are copied with
the pipe_to_file() actor, and not while waiting for more data on the
pipe.
splice: fix i_mutex locking in generic_splice_write()
Rearrange locking of i_mutex on destination so it's only held while
buffers are copied with the pipe_to_file() actor, and not while
waiting for more data on the pipe.
splice_from_pipe_next() will wait (if necessary) for more buffers to
be added to the pipe. splice_from_pipe_feed() will feed the buffers
to the supplied actor and return when there's no more data available
(or if all of the requested data has been copied).
This is necessary so that implementations can do locking around the
non-waiting splice_from_pipe_feed().
This patch should not cause any change in behavior.
blk_rq_unmap_user() returns -EFAULT if a program passes an invalid
address to kernel. SG_IO path needs to pass the returned value to user
space instead of ignoring it.
* topic/memdup_user:
ALSA: sound/pci: use memdup_user()
ALSA: sound/usb: use memdup_user()
ALSA: sound/isa: use memdup_user()
ALSA: sound/core: use memdup_user()
Merge branch 'master' of git://git.alsa-project.org/alsa-kernel into for-linus
* 'master' of git://git.alsa-project.org/alsa-kernel:
[ALSA] intel8x0: add one retry to the ac97_clock measurement routine
[ALSA] intel8x0: fix wrong conditions in ac97_clock measure routine
[ALSA] intel8x0: do not use zero value from PICB register
[ALSA] intel8x0: an attempt to make ac97_clock measurement more reliable
[ALSA] pcm-midlevel: Add more strict buffer position checks based on jiffies
[ALSA] hda_intel: fix unexpected ring buffer positions
In certain cases symlinks can appear to have zero size if a lookup
on the inode occurs within a certain (very short) time after the
symlink has been created. The symlink is correctly created on disk
but appears to have zero size when stat()ed. This patch closes the
race and prevents incorrect sizes appearing.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
cfq-iosched: don't delay queue kick for a merged request
"Zhang, Yanmin" <yanmin_zhang@linux.intel.com> reports that commit b029195dda0129b427c6e579a3bb3ae752da3a93 introduced a regression
of about 50% with sequential threaded read workloads. The test
case is:
tiotest -k0 -k1 -k3 -f 80 -t 32
which starts 32 threads each reading a 80MB file. Twiddle the kick
queue logic so that we do start IO immediately, if it appears to be
a fully merged request. We can't really detect that, so just check
if the request is bigger than a page or not. The assumption is that
since single bio issues will first queue a single request with just
one page attached and then later do merges on that, if we already
have more than a page worth of data in the request, then the request
is most likely good to go.
Verified that this doesn't cause a regression with the test case that
commit b029195dda0129b427c6e579a3bb3ae752da3a93 was fixing. It does not,
we still see maximum sized requests for the queue-then-merge cases.
buffer: switch do_emergency_thaw() away from pdflush_operation()
This is (again) a preparatory patch similar to commit a2a9537ac0b37a5da6fbe7e1e9cb06c524d2a9c4. It open codes a simple
async way of executing do_thaw_all() out of context, so we can get
rid of pdflush.
Sachin Sant [Tue, 14 Apr 2009 14:35:55 +0000 (14:35 +0000)]
powerpc: pseries/dtl.c should include asm/firmware.h
A randconfig build on powerpc failed with:
dtl.c: In function 'dtl_init':
dtl.c:238: error: implicit declaration of function 'firmware_has_feature'
dtl.c:238: error: 'FW_FEATURE_SPLPAR' undeclared (first use in this function)
- We need firmware.h for these definitions.
Signed-off-by: Sachin Sant <sachinp@in.ibm.com> Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
Paul Mackerras [Mon, 13 Apr 2009 14:09:09 +0000 (14:09 +0000)]
powerpc: Fix data-corrupting bug in __futex_atomic_op
Richard Henderson pointed out that the powerpc __futex_atomic_op has a
bug: it will write the wrong value if the stwcx. fails and it has to
retry the lwarx/stwcx. loop, since 'oparg' will have been overwritten
by the result from the first time around the loop. This happens
because it uses the same register for 'oparg' (an input) as it uses
for the result.
This fixes it by using separate registers for 'oparg' and 'ret'.
Cc: stable@kernel.org Signed-off-by: Paul Mackerras <paulus@samba.org>
Mike Mason [Fri, 10 Apr 2009 08:57:03 +0000 (08:57 +0000)]
powerpc/pseries: Set error_state to pci_channel_io_normal in eeh_report_reset()
While adding native EEH support to Emulex and Qlogic drivers, it was
discovered that dev->error_state was set to pci_io_channel_normal too
late in the recovery process. These drivers rely on error_state to
determine if they can access the device in their slot_reset callback,
thus error_state needs to be set to pci_io_channel_normal in
eeh_report_reset(). Below is a detailed explanation (courtesy of Richard
Lary) as to why this is necessary.
Background:
PCI MMIO or DMA accesses to a frozen slot generate additional EEH
errors. If the number of additional EEH errors exceeds EEH_MAX_FAILS the
adapter will be shutdown. To avoid triggering excessive EEH errors and
an undesirable adapter shutdown, some drivers use the
pci_channel_offline(dev) wrapper function to return a Boolean value
based on the value of pci_dev->error_state to determine if PCI MMIO or
DMA accesses are safe. If the wrapper returns TRUE, drivers must not
make PCI MMIO or DMA access to their hardware.
The pci_dev structure member error_state reflects one of three values,
1) pci_channel_io_normal, 2) pci_channel_io_frozen, 3)
pci_channel_io_perm_failure. Function pci_channel_offline(dev) returns
TRUE if error_state is pci_channel_io_frozen or pci_channel_io_perm_failure.
The EEH driver sets pci_dev->error_state to pci_channel_io_frozen at the
point where the PCI slot is frozen. Currently, the EEH driver restores
dev->error_state to pci_channel_io_normal in eeh_report_resume() before
calling the driver's resume callback. However, when the EEH driver calls
the driver's slot_reset callback() from eeh_report_reset(), it
incorrectly indicates the error state is still pci_channel_io_frozen.
Waiting until eeh_report_resume() to restore dev->error_state to
pci_channel_io_normal is too late for Emulex and QLogic FC drivers and
any other drivers which are designed to use common code paths in these
two cases: i) those called after the driver's slot_reset callback() and
ii) those called after the PCI slot is frozen but before the driver's
slot_reset callback is called. Case i) all driver paths executed to
reinitialize the hardware after a reset and case ii) all code paths
executed by driver kernel threads that run asynchronous to the main
driver thread, such as interrupt handlers and worker threads to process
driver work queues.
Emulex and QLogic FC drivers are designed with common code paths which
require that pci_channel_offline(dev) reflect the true state of the
hardware. The state transitions that the hardware takes from Normal
Operations to Slot Frozen to Reset to Normal Operations are documented
in the Power Architecture™ Platform Requirements+ (PAPR+) in Table 75.
PE State Control.
PAPR defines the following 3 states:
0 -- Not reset, Not EEH stopped, MMIO load/store allowed, DMA allowed
(Normal Operations)
1 -- Reset, Not EEH stopped, MMIO load/store disabled, DMA disabled
2 -- Not reset, EEH stopped, MMIO load/store disabled, DMA disabled
(Slot Frozen)
An EEH error places the slot in state 2 (Frozen) and the adapter driver
is notified that an EEH error was detected. If the adapter driver
returns PCI_ERS_RESULT_NEED_RESET, the EEH driver calls
eeh_reset_device() to place the slot into state 1 (Reset) and
eeh_reset_device completes by placing the slot into State 0 (Normal
Operations). Upon return from eeh_reset_device(), the EEH driver calls
eeh_report_reset, which then calls the adapter's slot_reset callback. At
the time the adapter's slot_reset callback is called, the true state of
the hardware is Normal Operations and should be accurately reflected by
setting dev->error_state to pci_channel_io_normal.
The current implementation of EEH driver does not do so and requires
this change to correct this deficiency.
Signed-off-by: Mike Mason <mmlnx@us.ibm.com> Acked-by: Linas Vepstas <linasvepstas@gmail.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
Merge branch 'drm-intel-next' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel
* 'drm-intel-next' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel:
drm/i915: fix scheduling while holding the new active list spinlock
drm/i915: Allow tiling of objects with bit 17 swizzling by the CPU.
drm/i915: Correctly set the write flag for get_user_pages in pread.
drm/i915: Fix use of uninitialized var in 40a5f0de
drm/i915: indicate framebuffer restore key in SysRq help message
drm/i915: sync hdmi detection by hdmi identifier with 2D
drm/i915: Fix a mismerge of the IGD patch (new .find_pll hooks missed)
drm/i915: Implement batch and ring buffer dumping
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