There is no need to put a function descriptor in
__secondary_hold_spinloop. Use ppc_function_entry to get the
instruction address and put it in __secondary_hold_spinloop instead.
Also fix an issue where we assumed cur_cpu_spec held a function
descriptor.
Signed-off-by: Anton Blanchard <anton@samba.org>
TRACE_WITH_FRAME_BUFFER creates 32 byte stack frames. On ppc64
ABIv1 this is too small and a callee could corrupt the stack by
writing to the parameter save area (starting at offset 48).
Signed-off-by: Anton Blanchard <anton@samba.org>
Some of the assembler files in lib/ make use of the fact that in the
ELFv1 ABI, the caller guarantees to provide stack space to save the
parameter registers r3 ... r10. This guarantee is no longer present
in ELFv2 for functions that have no variable argument list and no
more than 8 arguments.
Change the affected routines to temporarily store registers in the
red zone and/or the top of their own stack frame (in the space
provided to save r31 .. r29, which is actually not used in these
routines).
In opal_query_takeover, simply always allocate a stack frame;
the routine is not performance critical.
Signed-off-by: Ulrich Weigand <ulrich.weigand@de.ibm.com>
Signed-off-by: Anton Blanchard <anton@samba.org>
Change how we setup registers for ret_from_kernel_thread. In
ABIv1, instead of passing a function descriptor in, dereference
it and pass the target in directly.
Use ppc_global_function_entry to get it right on both ABIv1 and ABIv2.
Signed-off-by: Anton Blanchard <anton@samba.org>
The MMU hashtable and SLB branch patching code uses function
pointers for the update sites. This creates a difference between
ABIv1 and ABIv2 because we don't have function descriptors on
ABIv2.
Get rid of the function pointer and just point at the update
sites directly. This works on both ABIs.
Signed-off-by: Anton Blanchard <anton@samba.org>
To establish addressability quickly, ABIv2 requires the target
address of the function being called to be in r12. Fix a number of
places in assembly code that we do indirect function calls.
We need to avoid function descriptors on ABIv2 too.
Signed-off-by: Anton Blanchard <anton@samba.org>
ABIv2 doesn't have function descriptors or dot symbols. One
new thing it does add is a function global and a local entry
point, so add that to our _GLOBAL macro.
Signed-off-by: Anton Blanchard <anton@samba.org>
There are a few places we have to use dot symbols with the
current ABI - the syscall table and the kvm hcall table.
Wrap both of these with a new macro called DOTSYM so it will
be easy to transition away from dot symbols in a future ABI.
Signed-off-by: Anton Blanchard <anton@samba.org>
STD_EXCEPTION_COMMON, STD_EXCEPTION_COMMON_ASYNC and
MASKABLE_EXCEPTION branch to the handler, so we can remove
the explicit dot symbol and binutils will do the right thing.
Signed-off-by: Anton Blanchard <anton@samba.org>
There is no need to create a function descriptor for the system call
table. By using one we force the system call table into the text
section and it really belongs in the rodata section.
This also removes another use of dot symbols.
Signed-off-by: Anton Blanchard <anton@samba.org>
We have a number of places where we load the text address of a local
function and indirectly branch to it in assembly. Since it is an
indirect branch binutils will not know to use the function text
address, so that trick wont work.
There is no need for these functions to have a function descriptor
so we can replace it with a label and remove the dot symbol.
Signed-off-by: Anton Blanchard <anton@samba.org>
binutils is smart enough to know that a branch to a function
descriptor is actually a branch to the functions text address.
Alan tells me that binutils has been doing this for 9 years.
Signed-off-by: Anton Blanchard <anton@samba.org>
We avoid ABIv2 when building c files since commit b2ca8c89 (powerpc:
Don't use ELFv2 ABI to build the kernel). Do the same for assembly
files.
Signed-off-by: Anton Blanchard <anton@samba.org>
Pull slave-dmaengine fixes from Vinod Koul:
"Back from long weekend here in India and now the time to send fixes
for slave dmaengine.
- Dan's fix of sirf xlate code
- Jean's fix for timberland
- edma fixes by Sekhar for SG handling and Yuan for changing init
call"
* 'fixes' of git://git.infradead.org/users/vkoul/slave-dma:
dma: fix eDMA driver as a subsys_initcall
dmaengine: sirf: off by one in of_dma_sirfsoc_xlate()
platform: Fix timberdale dependencies
dma: edma: fix incorrect SG list handling
In the current version, when using perf record, if something goes
wrong in tools/perf/builtin-record.c:375
session = perf_session__new(file, false, NULL);
The error message:
"Not enough memory for reading per file header"
is issued. This error message seems to be outdated and is not very
helpful. This patch proposes to replace this error message by
"Perf session creation failed"
I believe this issue has been brought to lkml:
https://lkml.org/lkml/2014/2/24/458
although this patch only tackles a (small) part of the issue.
Additionnaly, this patch improves error reporting in
tools/perf/util/data.c open_file_write.
Currently, if the call to open fails, the user is unaware of it.
This patch logs the error, before returning the error code to
the caller.
Reported-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Adrien BAK <adrien.bak@metascale.org>
Link: http://lkml.kernel.org/r/1397786443.3093.4.camel@beast
[ Reorganize the changelog into paragraphs ]
[ Added empty line after fd declaration in open_file_write ]
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
pert-report doesn't resolve function names in VDSO:
$ perf report --stdio -g flat,0.0,15,callee --sort pid
...
8.76%
0x7fff6b1fe861
__gettimeofday
ACE_OS::gettimeofday()
...
In this case symbol values should be adjusted the same way as for executables,
relocatable objects and prelinked libraries.
After fix:
$ perf report --stdio -g flat,0.0,15,callee --sort pid
...
8.76%
__vdso_gettimeofday
__gettimeofday
ACE_OS::gettimeofday()
Signed-off-by: Vladimir Nikulichev <nvs@tbricks.com>
Tested-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Link: http://lkml.kernel.org/r/969812.163009436-sendEmail@nvs
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Every event in the perf-kvm has a 'stats' structure, which contains
max/min/average/etc times of handling this event.
The problem is that the 'perf-kvm stat report' command always shows
that 'min time' is 0us for every event. Example:
# perf kvm stat report
Analyze events for all VCPUs:
VM-EXIT Samples Samples% Time% Min Time Max Time Avg time
[..]
0xB2 MSCH 12 0.07% 0.00% 0us 8us 7.31us ( +- 2.11% )
0xB2 CHSC 12 0.07% 0.00% 0us 18us 9.39us ( +- 9.49% )
0xB2 STPX 8 0.05% 0.00% 0us 2us 1.88us ( +- 7.18% )
0xB2 STSI 7 0.04% 0.00% 0us 44us 16.49us ( +- 38.20% )
[..]
This happens because the 'stats' structure is not initialized and
stats->min equals to 0. Lets initialize the structure for every
event after its allocation using init_stats() function. This initializes
stats->min to -1 and makes 'Min time' statistics counting work:
# perf kvm stat report
Analyze events for all VCPUs:
VM-EXIT Samples Samples% Time% Min Time Max Time Avg time
[..]
0xB2 MSCH 12 0.07% 0.00% 6us 8us 7.31us ( +- 2.11% )
0xB2 CHSC 12 0.07% 0.00% 7us 18us 9.39us ( +- 9.49% )
0xB2 STPX 8 0.05% 0.00% 1us 2us 1.88us ( +- 7.18% )
0xB2 STSI 7 0.04% 0.00% 1us 44us 16.49us ( +- 38.20% )
[..]
Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Link: http://lkml.kernel.org/r/1397053319-2130-3-git-send-email-borntraeger@de.ibm.com
[ Fixing the perf examples changelog output ]
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Pull x86 fix from Ingo Molnar:
"This fixes the preemption-count imbalance crash reported by Owen
Kibel"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mce: Fix CMCI preemption bugs
Pull drm fixes from Dave Airlie:
"Unfortunately this contains no easter eggs, its a bit larger than I'd
like, but I included a patch that just moves code from one file to
another and I'd like to avoid merge conflicts with that later, so it
makes it seem worse than it is,
Otherwise:
- radeon: fixes to use new microcode to stabilise some cards, use
some common displayport code, some runtime pm fixes, pll regression
fixes
- i915: fix for some context oopses, a warn in a used path, backlight
fixes
- nouveau: regression fix
- omap: a bunch of fixes"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (51 commits)
drm: bochs: drop unused struct fields
drm: bochs: add power management support
drm: cirrus: add power management support
drm: Split out drm_probe_helper.c from drm_crtc_helper.c
drm/plane-helper: Don't fake-implement primary plane disabling
drm/ast: fix value check in cbr_scan2
drm/nouveau/bios: fix a bit shift error introduced by 457e77b
drm/radeon/ci: make sure mc ucode is loaded before checking the size
drm/radeon/si: make sure mc ucode is loaded before checking the size
drm/radeon: improve PLL params if we don't match exactly v2
drm/radeon: memory leak on bo reservation failure. v2
drm/radeon: fix VCE fence command
drm/radeon: re-enable mclk dpm on R7 260X asics
drm/radeon: add support for newer mc ucode on CI (v2)
drm/radeon: add support for newer mc ucode on SI (v2)
drm/radeon: apply more strict limits for PLL params v2
drm/radeon: update CI DPM powertune settings
drm/radeon: fix runpm handling on APUs (v4)
drm/radeon: disable mclk dpm on R7 260X
drm/tegra: Remove gratuitous pad field
...
Some i2c fixes over DisplayPort.
* 'drm-next-3.15-wip' of git://people.freedesktop.org/~deathsimple/linux:
drm/radeon: Improve vramlimit module param documentation
drm/radeon: fix audio pin counts for DCE6+ (v2)
drm/radeon/dp: switch to the common i2c over aux code
drm/dp/i2c: Update comments about common i2c over dp assumptions (v3)
drm/dp/i2c: send bare addresses to properly reset i2c connections (v4)
drm/radeon/dp: handle zero sized i2c over aux transactions (v2)
drm/i915: support address only i2c-over-aux transactions
drm/tegra: dp: Support address-only I2C-over-AUX transactions
Pull more networking fixes from David Miller:
1) Fix mlx4_en_netpoll implementation, it needs to schedule a NAPI
context, not synchronize it. From Chris Mason.
2) Ipv4 flow input interface should never be zero, it should be
LOOPBACK_IFINDEX instead. From Cong Wang and Julian Anastasov.
3) Properly configure MAC to PHY connection in mvneta devices, from
Thomas Petazzoni.
4) sys_recv should use SYSCALL_DEFINE. From Jan Glauber.
5) Tunnel driver ioctls do not use the correct namespace, fix from
Nicolas Dichtel.
6) Fix memory leak on seccomp filter attach, from Kees Cook.
7) Fix lockdep warning for nested vlans, from Ding Tianhong.
8) Crashes can happen in SCTP due to how the auth_enable value is
managed, fix from Vlad Yasevich.
9) Wireless fixes from John W Linville and co.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (45 commits)
net: sctp: cache auth_enable per endpoint
tg3: update rx_jumbo_pending ring param only when jumbo frames are enabled
vlan: Fix lockdep warning when vlan dev handle notification
seccomp: fix memory leak on filter attach
isdn: icn: buffer overflow in icn_command()
ip6_tunnel: use the right netns in ioctl handler
sit: use the right netns in ioctl handler
ip_tunnel: use the right netns in ioctl handler
net: use SYSCALL_DEFINEx for sys_recv
net: mdio-gpio: Add support for separate MDI and MDO gpio pins
net: mdio-gpio: Add support for active low gpio pins
net: mdio-gpio: Use devm_ functions where possible
ipv4, route: pass 0 instead of LOOPBACK_IFINDEX to fib_validate_source()
ipv4, fib: pass LOOPBACK_IFINDEX instead of 0 to flowi4_iif
mlx4_en: don't use napi_synchronize inside mlx4_en_netpoll
net: mvneta: properly configure the MAC <-> PHY connection in all situations
net: phy: add minimal support for QSGMII PHY
sfc:On MCDI timeout, issue an FLR (and mark MCDI to fail-fast)
mwifiex: fix hung task on command timeout
mwifiex: process event before command response
...
Pull cifs fixes from Steve French:
"A set of 5 small cifs fixes"
* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
cif: fix dead code
cifs: fix error handling cifs_user_readv
fs: cifs: remove unused variable.
Return correct error on query of xattr on file with empty xattrs
cifs: Wait for writebacks to complete before attempting write.
Here are a few driver fixes for char/misc drivers that resolve reported
issues.
All have been in linux-next successfully for a few days.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-3.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver fixes from Greg KH:
"Here are a few driver fixes for char/misc drivers that resolve
reported issues.
All have been in linux-next successfully for a few days"
* tag 'char-misc-3.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
Drivers: hv: vmbus: Negotiate version 3.0 when running on ws2012r2 hosts
Tools: hv: Handle the case when the target file exists correctly
vme_tsi148: Utilize to_pci_dev() macro
vme_tsi148: Fix PCI address mapping assumption
vme_tsi148: Fix typo in tsi148_slave_get()
w1: avoid recursive device_add
w1: fix netlink refcnt leak on error path
misc: Grammar s/addition/additional/
drivers: mcb: fix memory leak in chameleon_parse_cells() error path
mei: ignore client writing state during cb completion
mei: me: do not load the driver if the FW doesn't support MEI interface
GenWQE: Increase driver version number
GenWQE: Fix multithreading problems
GenWQE: Ensure rc is not returning an uninitialized value
GenWQE: Add wmb before DDCB is started
GenWQE: Enable access to VPD flash area
Here are some driver core fixes for 3.15-rc2. Also in here are some
documentation updates, as well as an API removal that had to wait for
after -rc1 due to the cleanups coming into you from multiple developer
trees (this one and the PPC tree.)
All have been in linux next successfully.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core fixes from Greg KH:
"Here are some driver core fixes for 3.15-rc2. Also in here are some
documentation updates, as well as an API removal that had to wait for
after -rc1 due to the cleanups coming into you from multiple developer
trees (this one and the PPC tree.)
All have been in linux next successfully"
* tag 'driver-core-3.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
drivers/base/dd.c incorrect pr_debug() parameters
Documentation: Update stable address in Chinese and Japanese translations
topology: Fix compilation warning when not in SMP
Chinese: add translation of io_ordering.txt
stable_kernel_rules: spelling/word usage
sysfs, driver-core: remove unused {sysfs|device}_schedule_callback_owner()
kernfs: protect lazy kernfs_iattrs allocation with mutex
fs: Don't return 0 from get_anon_bdev
Here are a few staging driver fixes for issues that have been reported
for 3.15-rc2.
Also dominating the diffstat for the pull request is the removal of the
rtl8187se driver. It's no longer needed in staging as a "real" driver
for this hardware is now merged in the tree in the "correct" location in
drivers/net/
All of these patches have been tested in linux-next.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-3.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging driver fixes from Greg KH:
"Here are a few staging driver fixes for issues that have been reported
for 3.15-rc2.
Also dominating the diffstat for the pull request is the removal of
the rtl8187se driver. It's no longer needed in staging as a "real"
driver for this hardware is now merged in the tree in the "correct"
location in drivers/net/
All of these patches have been tested in linux-next"
* tag 'staging-3.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
staging: r8188eu: Fix case where ethtype was never obtained and always be checked against 0
staging: r8712u: Fix case where ethtype was never obtained and always be checked against 0
staging: r8188eu: Calling rtw_get_stainfo() with a NULL sta_addr will return NULL
staging: comedi: fix circular locking dependency in comedi_mmap()
staging: r8723au: Add missing initialization of change_inx in sort algorithm
Staging: unisys: use after free in list_for_each()
staging: unisys: use after free in error messages
staging: speakup: fix misuse of kstrtol() in handle_goto()
staging: goldfish: Call free_irq in error path
staging: delete rtl8187se wireless driver
staging: rtl8723au: Fix buffer overflow in rtw_get_wfd_ie()
staging: gs_fpgaboot: remove __TIMESTAMP__ macro
staging: vme: fix memory leak in vme_user_probe()
staging: fpgaboot: clean up Makefile
staging/usbip: fix store_attach() sscanf return value check
staging/usbip: userspace - fix usbipd SIGSEGV from refresh_exported_devices()
staging: rtl8188eu: remove spaces, correct counts to unbreak P2P ioctls
staging/rtl8821ae: Fix OOM handling in _rtl_init_deferred_work()
Here are a number of small tty/serial driver fixes for 3.15-rc2. Also
in here are some Documentation file removals for drivers that we removed
a long time ago, no need to keep it around any longer.
All of these have been in linux-next for a bit.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-3.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver fixes from Greg KH:
"Here are a number of small tty/serial driver fixes for 3.15-rc2. Also
in here are some Documentation file removals for drivers that we
removed a long time ago, no need to keep it around any longer.
All of these have been in linux-next for a bit"
* tag 'tty-3.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
Revert "serial: 8250, disable "too much work" messages"
serial: amba-pl011: fix regression, causing an Oops on rmmod
tty: Fix help text of SYNCLINK_CS
tty: fix memleak in alloc_pid
ttyprintk: Allow built as a module
ttyprintk: Fix wrong tty_unregister_driver() call in the error path
serial: 8250, disable "too much work" messages
Documentation/serial: Delete obsolete driver documentation
serial: omap: Fix missing pm_runtime_resume handling by simplifying code
serial_core: Fix pm imbalance on unbind
serial: pl011: change Rx burst size to half of trigger level
serial: timberdale: Depend on X86_32
serial: st-asc: Fix SysRq char handling
Revert "serial: clps711x: Give a chance to perform useful tasks during wait loop"
serial_core: Fix conditional start_tx on ring buffer not empty
serial: efm32: use $vendor,$device scheme for compatible string
serial: omap: free the wakeup settings in remove
Here are a number of tiny USB fixes and new device ids for 3.15-rc2.
Nothing major, just issues some people have reported.
All of these have been in linux-next.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-3.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB fixes from Greg KH:
"Here are a number of tiny USB fixes and new device ids for 3.15-rc2.
Nothing major, just issues some people have reported.
All of these have been in linux-next"
* tag 'usb-3.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
uas: fix deadlocky memory allocations
uas: fix error handling during scsi_scan()
uas: fix GFP_NOIO under spinlock
uwb: adds missing error handling
USB: cdc-acm: Remove Motorola/Telit H24 serial interfaces from ACM driver
USB: ohci-jz4740: FEAT_POWER is a port feature, not a hub feature
USB: ohci-jz4740: Fix uninitialized variable warning
USB: EHCI: tegra: set txfill_tuning
usb: ehci-platform: Return immediately from suspend if ehci_suspend fails
usb: ehci-exynos: Return immediately from suspend if ehci_suspend fails
USB: fix crash during hotplug of PCI USB controller card
USB: cdc-acm: fix double usb_autopm_put_interface() in acm_port_activate()
usb: usb-common: fix typo for usb_state_string
USB: usb_wwan: fix handling of missing bulk endpoints
USB: pl2303: add ids for Hewlett-Packard HP POS pole displays
USB: cp210x: Add 8281 (Nanotec Plug & Drive)
usb: option driver, add support for Telit UE910v2
Revert "USB: serial: add usbid for dell wwan card to sierra.c"
USB: serial: ftdi_sio: add id for Brainboxes serial cards
Merge misc fixes from Andrew Morton:
"13 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
thp: close race between split and zap huge pages
mm: fix new kernel-doc warning in filemap.c
mm: fix CONFIG_DEBUG_VM_RB description
mm: use paravirt friendly ops for NUMA hinting ptes
mips: export flush_icache_range
mm/hugetlb.c: add cond_resched_lock() in return_unused_surplus_pages()
wait: explain the shadowing and type inconsistencies
Shiraz has moved
Documentation/vm/numa_memory_policy.txt: fix wrong document in numa_memory_policy.txt
powerpc/mm: fix ".__node_distance" undefined
kernel/watchdog.c:touch_softlockup_watchdog(): use raw_cpu_write()
init/Kconfig: move the trusted keyring config option to general setup
vmscan: reclaim_clean_pages_from_list() must use mod_zone_page_state()
Sasha Levin has reported two THP BUGs[1][2]. I believe both of them
have the same root cause. Let's look to them one by one.
The first bug[1] is "kernel BUG at mm/huge_memory.c:1829!". It's
BUG_ON(mapcount != page_mapcount(page)) in __split_huge_page(). From my
testing I see that page_mapcount() is higher than mapcount here.
I think it happens due to race between zap_huge_pmd() and
page_check_address_pmd(). page_check_address_pmd() misses PMD which is
under zap:
CPU0 CPU1
zap_huge_pmd()
pmdp_get_and_clear()
__split_huge_page()
anon_vma_interval_tree_foreach()
__split_huge_page_splitting()
page_check_address_pmd()
mm_find_pmd()
/*
* We check if PMD present without taking ptl: no
* serialization against zap_huge_pmd(). We miss this PMD,
* it's not accounted to 'mapcount' in __split_huge_page().
*/
pmd_present(pmd) == 0
BUG_ON(mapcount != page_mapcount(page)) // CRASH!!!
page_remove_rmap(page)
atomic_add_negative(-1, &page->_mapcount)
The second bug[2] is "kernel BUG at mm/huge_memory.c:1371!".
It's VM_BUG_ON_PAGE(!PageHead(page), page) in zap_huge_pmd().
This happens in similar way:
CPU0 CPU1
zap_huge_pmd()
pmdp_get_and_clear()
page_remove_rmap(page)
atomic_add_negative(-1, &page->_mapcount)
__split_huge_page()
anon_vma_interval_tree_foreach()
__split_huge_page_splitting()
page_check_address_pmd()
mm_find_pmd()
pmd_present(pmd) == 0 /* The same comment as above */
/*
* No crash this time since we already decremented page->_mapcount in
* zap_huge_pmd().
*/
BUG_ON(mapcount != page_mapcount(page))
/*
* We split the compound page here into small pages without
* serialization against zap_huge_pmd()
*/
__split_huge_page_refcount()
VM_BUG_ON_PAGE(!PageHead(page), page); // CRASH!!!
So my understanding the problem is pmd_present() check in mm_find_pmd()
without taking page table lock.
The bug was introduced by me commit with commit 117b0791ac. Sorry for
that. :(
Let's open code mm_find_pmd() in page_check_address_pmd() and do the
check under page table lock.
Note that __page_check_address() does the same for PTE entires
if sync != 0.
I've stress tested split and zap code paths for 36+ hours by now and
don't see crashes with the patch applied. Before it took <20 min to
trigger the first bug and few hours for second one (if we ignore
first).
[1] https://lkml.kernel.org/g/<53440991.9090001@oracle.com>
[2] https://lkml.kernel.org/g/<5310C56C.60709@oracle.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Bob Liu <lliubbo@gmail.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michel Lespinasse <walken@google.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org> [3.13+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix new kernel-doc warning in mm/filemap.c:
Warning(mm/filemap.c:2600): Excess function parameter 'ppos' description in '__generic_file_aio_write'
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This appears to be a copy/paste error. Update the description to
reflect extra rbtree debug and checks for the config option instead of
duplicating CONFIG_DEBUG_VM.
Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Cc: Aswin Chandramouleeswaran <aswin@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Vrabel identified a regression when using automatic NUMA balancing
under Xen whereby page table entries were getting corrupted due to the
use of native PTE operations. Quoting him
Xen PV guest page tables require that their entries use machine
addresses if the preset bit (_PAGE_PRESENT) is set, and (for
successful migration) non-present PTEs must use pseudo-physical
addresses. This is because on migration MFNs in present PTEs are
translated to PFNs (canonicalised) so they may be translated back
to the new MFN in the destination domain (uncanonicalised).
pte_mknonnuma(), pmd_mknonnuma(), pte_mknuma() and pmd_mknuma()
set and clear the _PAGE_PRESENT bit using pte_set_flags(),
pte_clear_flags(), etc.
In a Xen PV guest, these functions must translate MFNs to PFNs
when clearing _PAGE_PRESENT and translate PFNs to MFNs when setting
_PAGE_PRESENT.
His suggested fix converted p[te|md]_[set|clear]_flags to using
paravirt-friendly ops but this is overkill. He suggested an alternative
of using p[te|md]_modify in the NUMA page table operations but this is
does more work than necessary and would require looking up a VMA for
protections.
This patch modifies the NUMA page table operations to use paravirt
friendly operations to set/clear the flags of interest. Unfortunately
this will take a performance hit when updating the PTEs on
CONFIG_PARAVIRT but I do not see a way around it that does not break
Xen.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: David Vrabel <david.vrabel@citrix.com>
Tested-by: David Vrabel <david.vrabel@citrix.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Noonan <steven@uplinklabs.net>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
