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Linux kernel
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Pull libnvdimm fixes from Dan Williams:
"A small batch of fixes for v4.20-rc3.
The overflow continuation fix addresses something that has been broken
for several releases. Arguably it could wait even longer, but it's a
one line fix and this finishes the last of the known address range
scrub bug reports. The revert addresses a lockdep regression. The unit
tests are not critical to fix, but no reason to hold this fix back.
Summary:
- Address Range Scrub overflow continuation handling has been broken
since it was initially merged. It was only recently that error
injection and platform-BIOS support enabled this corner case to be
exercised.
- The recent attempt to provide more isolation for the kernel Address
Range Scrub state machine from userapace initiated sessions
triggers a lockdep report. Revert and try again at the next merge
window.
- Fix a kasan reported buffer overflow in libnvdimm unit test
infrastrucutre (nfit_test)"
* tag 'libnvdimm-fixes-4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
Revert "acpi, nfit: Further restrict userspace ARS start requests"
acpi, nfit: Fix ARS overflow continuation
tools/testing/nvdimm: Fix the array size for dimm devices.
Merge misc fixes from Andrew Morton:
"16 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm/memblock.c: fix a typo in __next_mem_pfn_range() comments
mm, page_alloc: check for max order in hot path
scripts/spdxcheck.py: make python3 compliant
tmpfs: make lseek(SEEK_DATA/SEK_HOLE) return ENXIO with a negative offset
lib/ubsan.c: don't mark __ubsan_handle_builtin_unreachable as noreturn
mm/vmstat.c: fix NUMA statistics updates
mm/gup.c: fix follow_page_mask() kerneldoc comment
ocfs2: free up write context when direct IO failed
scripts/faddr2line: fix location of start_kernel in comment
mm: don't reclaim inodes with many attached pages
mm, memory_hotplug: check zone_movable in has_unmovable_pages
mm/swapfile.c: use kvzalloc for swap_info_struct allocation
MAINTAINERS: update OMAP MMC entry
hugetlbfs: fix kernel BUG at fs/hugetlbfs/inode.c:444!
kernel/sched/psi.c: simplify cgroup_move_task()
z3fold: fix possible reclaim races
The following lockdep splat results from acquiring the init_mutex in
acpi_nfit_clear_to_send():
WARNING: possible circular locking dependency detected
lt-daxdev-error/7216 is trying to acquire lock:
00000000f694db15 (&acpi_desc->init_mutex){+.+.}, at: acpi_nfit_clear_to_send+0x27/0x80 [nfit]
but task is already holding lock:
00000000182298f2 (&nvdimm_bus->reconfig_mutex){+.+.}, at: __nd_ioctl+0x457/0x610 [libnvdimm]
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&nvdimm_bus->reconfig_mutex){+.+.}:
nvdimm_badblocks_populate+0x41/0x150 [libnvdimm]
nd_region_notify+0x95/0xb0 [libnvdimm]
nd_device_notify+0x40/0x50 [libnvdimm]
ars_complete+0x7f/0xd0 [nfit]
acpi_nfit_scrub+0xbb/0x410 [nfit]
process_one_work+0x22b/0x5c0
worker_thread+0x3c/0x390
kthread+0x11e/0x140
ret_from_fork+0x3a/0x50
-> #0 (&acpi_desc->init_mutex){+.+.}:
__mutex_lock+0x83/0x980
acpi_nfit_clear_to_send+0x27/0x80 [nfit]
__nd_ioctl+0x474/0x610 [libnvdimm]
nd_ioctl+0xa4/0xb0 [libnvdimm]
do_vfs_ioctl+0xa5/0x6e0
ksys_ioctl+0x70/0x80
__x64_sys_ioctl+0x16/0x20
do_syscall_64+0x60/0x210
entry_SYSCALL_64_after_hwframe+0x49/0xbe
New infrastructure is needed to be able to perform this check without
acquiring the lock.
Fixes: 594861215c83 ("acpi, nfit: Further restrict userspace ARS start")
Cc: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull scheduler fix from Ingo Molnar:
"Fix an exec() related scalability/performance regression, which was
caused by incorrectly calculating load and migrating tasks on exec()
when they shouldn't be"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Fix cpu_util_wake() for 'execl' type workloads
Link: http://lkml.kernel.org/r/20181107100247.13359-1-rainccrun@gmail.com
Signed-off-by: Chen Chang <rainccrun@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When the platform BIOS is unable to report all the media error records
it requires the OS to restart the scrub at a prescribed location. The
driver detects the overflow condition, but then fails to report it to
the ARS state machine after reaping the records. Propagate -ENOSPC
correctly to continue the ARS operation.
Cc: <stable@vger.kernel.org>
Fixes: 1cf03c00e7c1 ("nfit: scrub and register regions in a workqueue")
Reported-by: Jacek Zloch <jacek.zloch@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull perf fixes from Ingo Molnar:
"Fix uncore PMU enumeration for CofeeLake CPUs"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel/uncore: Support CoffeeLake 8th CBOX
perf/x86/intel/uncore: Add more IMC PCI IDs for KabyLake and CoffeeLake CPUs
A ~10% regression has been reported for UnixBench's execl throughput
test by Aaron Lu and Ye Xiaolong:
https://lkml.org/lkml/2018/10/30/765
That test is pretty simple, it does a "recursive" execve() syscall on the
same binary. Starting from the syscall, this sequence is possible:
do_execve()
do_execveat_common()
__do_execve_file()
sched_exec()
select_task_rq_fair() <==| Task already enqueued
find_idlest_cpu()
find_idlest_group()
capacity_spare_wake() <==| Functions not called from
cpu_util_wake() | the wakeup path
which means we can end up calling cpu_util_wake() not only from the
"wakeup path", as its name would suggest. Indeed, the task doing an
execve() syscall is already enqueued on the CPU we want to get the
cpu_util_wake() for.
The estimated utilization for a CPU computed in cpu_util_wake() was
written under the assumption that function can be called only from the
wakeup path. If instead the task is already enqueued, we end up with a
utilization which does not remove the current task's contribution from
the estimated utilization of the CPU.
This will wrongly assume a reduced spare capacity on the current CPU and
increase the chances to migrate the task on execve.
The regression is tracked down to:
commit d519329f72a6 ("sched/fair: Update util_est only on util_avg updates")
because in that patch we turn on by default the UTIL_EST sched feature.
However, the real issue is introduced by:
commit f9be3e5961c5 ("sched/fair: Use util_est in LB and WU paths")
Let's fix this by ensuring to always discount the task estimated
utilization from the CPU's estimated utilization when the task is also
the current one. The same benchmark of the bug report, executed on a
dual socket 40 CPUs Intel(R) Xeon(R) CPU E5-2690 v2 @ 3.00GHz machine,
reports these "Execl Throughput" figures (higher the better):
mainline : 48136.5 lps
mainline+fix : 55376.5 lps
which correspond to a 15% speedup.
Moreover, since {cpu_util,capacity_spare}_wake() are not really only
used from the wakeup path, let's remove this ambiguity by using a better
matching name: {cpu_util,capacity_spare}_without().
Since we are at that, let's also improve the existing documentation.
Reported-by: Aaron Lu <aaron.lu@intel.com>
Reported-by: Ye Xiaolong <xiaolong.ye@intel.com>
Tested-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Perret <quentin.perret@arm.com>
Cc: Steve Muckle <smuckle@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Todd Kjos <tkjos@google.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Fixes: f9be3e5961c5 (sched/fair: Use util_est in LB and WU paths)
Link: https://lore.kernel.org/lkml/20181025093100.GB13236@e110439-lin/
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Konstantin has noticed that kvmalloc might trigger the following
warning:
WARNING: CPU: 0 PID: 6676 at mm/vmstat.c:986 __fragmentation_index+0x54/0x60
[...]
Call Trace:
fragmentation_index+0x76/0x90
compaction_suitable+0x4f/0xf0
shrink_node+0x295/0x310
node_reclaim+0x205/0x250
get_page_from_freelist+0x649/0xad0
__alloc_pages_nodemask+0x12a/0x2a0
kmalloc_large_node+0x47/0x90
__kmalloc_node+0x22b/0x2e0
kvmalloc_node+0x3e/0x70
xt_alloc_table_info+0x3a/0x80 [x_tables]
do_ip6t_set_ctl+0xcd/0x1c0 [ip6_tables]
nf_setsockopt+0x44/0x60
SyS_setsockopt+0x6f/0xc0
do_syscall_64+0x67/0x120
entry_SYSCALL_64_after_hwframe+0x3d/0xa2
the problem is that we only check for an out of bound order in the slow
path and the node reclaim might happen from the fast path already. This
is fixable by making sure that kvmalloc doesn't ever use kmalloc for
requests that are larger than KMALLOC_MAX_SIZE but this also shows that
the code is rather fragile. A recent UBSAN report just underlines that
by the following report
UBSAN: Undefined behaviour in mm/page_alloc.c:3117:19
shift exponent 51 is too large for 32-bit type 'int'
CPU: 0 PID: 6520 Comm: syz-executor1 Not tainted 4.19.0-rc2 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0xd2/0x148 lib/dump_stack.c:113
ubsan_epilogue+0x12/0x94 lib/ubsan.c:159
__ubsan_handle_shift_out_of_bounds+0x2b6/0x30b lib/ubsan.c:425
__zone_watermark_ok+0x2c7/0x400 mm/page_alloc.c:3117
zone_watermark_fast mm/page_alloc.c:3216 [inline]
get_page_from_freelist+0xc49/0x44c0 mm/page_alloc.c:3300
__alloc_pages_nodemask+0x21e/0x640 mm/page_alloc.c:4370
alloc_pages_current+0xcc/0x210 mm/mempolicy.c:2093
alloc_pages include/linux/gfp.h:509 [inline]
__get_free_pages+0x12/0x60 mm/page_alloc.c:4414
dma_mem_alloc+0x36/0x50 arch/x86/include/asm/floppy.h:156
raw_cmd_copyin drivers/block/floppy.c:3159 [inline]
raw_cmd_ioctl drivers/block/floppy.c:3206 [inline]
fd_locked_ioctl+0xa00/0x2c10 drivers/block/floppy.c:3544
fd_ioctl+0x40/0x60 drivers/block/floppy.c:3571
__blkdev_driver_ioctl block/ioctl.c:303 [inline]
blkdev_ioctl+0xb3c/0x1a30 block/ioctl.c:601
block_ioctl+0x105/0x150 fs/block_dev.c:1883
vfs_ioctl fs/ioctl.c:46 [inline]
do_vfs_ioctl+0x1c0/0x1150 fs/ioctl.c:687
ksys_ioctl+0x9e/0xb0 fs/ioctl.c:702
__do_sys_ioctl fs/ioctl.c:709 [inline]
__se_sys_ioctl fs/ioctl.c:707 [inline]
__x64_sys_ioctl+0x7e/0xc0 fs/ioctl.c:707
do_syscall_64+0xc4/0x510 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Note that this is not a kvmalloc path. It is just that the fast path
really depends on having sanitzed order as well. Therefore move the
order check to the fast path.
Link: http://lkml.kernel.org/r/20181113094305.GM15120@dhcp22.suse.cz
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reported-by: Kyungtae Kim <kt0755@gmail.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Pavel Tatashin <pavel.tatashin@microsoft.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Aaron Lu <aaron.lu@intel.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Byoungyoung Lee <lifeasageek@gmail.com>
Cc: "Dae R. Jeong" <threeearcat@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
KASAN reports following global out of bounds access while
nfit_test is being loaded. The out of bound access happens
the following reference to dimm_fail_cmd_flags[dimm]. 'dimm' is
over than the index value, NUM_DCR (==5).
static int override_return_code(int dimm, unsigned int func, int rc)
{
if ((1 << func) & dimm_fail_cmd_flags[dimm]) {
dimm_fail_cmd_flags[] definition:
static unsigned long dimm_fail_cmd_flags[NUM_DCR];
'dimm' is the return value of get_dimm(), and get_dimm() returns
the index of handle[] array. The handle[] has 7 index. Let's use
ARRAY_SIZE(handle) as the array size.
KASAN report:
==================================================================
BUG: KASAN: global-out-of-bounds in nfit_test_ctl+0x47bb/0x55b0 [nfit_test]
Read of size 8 at addr ffffffffc10cbbe8 by task kworker/u41:0/8
...
Call Trace:
dump_stack+0xea/0x1b0
? dump_stack_print_info.cold.0+0x1b/0x1b
? kmsg_dump_rewind_nolock+0xd9/0xd9
print_address_description+0x65/0x22e
? nfit_test_ctl+0x47bb/0x55b0 [nfit_test]
kasan_report.cold.6+0x92/0x1a6
nfit_test_ctl+0x47bb/0x55b0 [nfit_test]
...
The buggy address belongs to the variable:
dimm_fail_cmd_flags+0x28/0xffffffffffffa440 [nfit_test]
==================================================================
Fixes: 39611e83a28c ("tools/testing/nvdimm: Make DSM failure code injection...")
Signed-off-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull EFI fixes from Ingo Molnar:
"Misc fixes: two warning splat fixes, a leak fix and persistent memory
allocation fixes for ARM"
* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi: Permit calling efi_mem_reserve_persistent() from atomic context
efi/arm: Defer persistent reservations until after paging_init()
efi/arm/libstub: Pack FDT after populating it
efi/arm: Revert deferred unmap of early memmap mapping
efi: Fix debugobjects warning on 'efi_rts_work'
Coffee Lake has 8 core products which has 8 Cboxes. The 8th CBOX is
mapped into different MSR space.
Increase the num_boxes to 8 to handle the new products. It will not
impact the previous platforms, SkyLake, KabyLake and earlier CoffeeLake.
Because the num_boxes will be recalculated in uncore_cpu_init and
doesn't exceed the x86_max_cores.
Introduce a new box flag bit to indicate the 8th CBOX.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/20181019170419.378-2-kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Duplicated 'case it'.
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Reviewed-by: Xi Xu <xu.xi8@zte.com.cn>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: zhong.weidong@zte.com.cn
Link: http://lkml.kernel.org/r/1541379013-11352-1-git-send-email-wang.yi59@zte.com.cn
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Without this change the following happens when using Python3 (3.6.6):
$ echo "GPL-2.0" | python3 scripts/spdxcheck.py -
FAIL: 'str' object has no attribute 'decode'
Traceback (most recent call last):
File "scripts/spdxcheck.py", line 253, in <module>
parser.parse_lines(sys.stdin, args.maxlines, '-')
File "scripts/spdxcheck.py", line 171, in parse_lines
line = line.decode(locale.getpreferredencoding(False), errors='ignore')
AttributeError: 'str' object has no attribute 'decode'
So as the line is already a string, there is no need to decode it and
the line can be dropped.
/usr/bin/python on Arch is Python 3. So this would indeed be worth
going into 4.19.
Link: http://lkml.kernel.org/r/20181023070802.22558-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Joe Perches <joe@perches.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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