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Linux kernel
============
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There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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Pull perf fixes from Thomas Gleixner:
"A pile of perf updates:
- Fix broken sanity check in the /proc/sys/kernel/perf_cpu_time_max_percent
write handler
- Cure a perf script crash which caused by an unitinialized data
structure
- Highlight the hottest instruction in perf top and not a random one
- Cure yet another clang issue when building perf python
- Handle topology entries with no CPU correctly in the tools
- Handle perf data which contains both tracepoints and performance
counter entries correctly.
- Add a missing NULL pointer check in perf ordered_events_free()"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf script: Fix crash when processing recorded stat data
perf top: Fix wrong hottest instruction highlighted
perf tools: Handle TOPOLOGY headers with no CPU
perf python: Remove -fstack-clash-protection when building with some clang versions
perf core: Fix perf_proc_update_handler() bug
perf script: Fix crash with printing mixed trace point and other events
perf ordered_events: Fix crash in ordered_events__free
Pull EFI fix from Thomas Gleixner:
"The dump info for the efi page table debugging lacks a terminator
which causes the kernel to crash when the debugfile is read"
* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi/arm64: Fix debugfs crash by adding a terminator for ptdump marker
Pull perf/urgent fixes from Arnaldo Carvalho de Melo:
Kernel:
Stephane Eranian:
- Fix perf_proc_update_handler() bug.
perf script:
Andi Kleen:
- Fix crash with printing mixed trace point and other events.
Tony Jones:
- Fix crash when processing recorded stat data.
perf top:
He Kuang:
- Fix wrong hottest instruction highlighted.
perf python:
Arnaldo Carvalho de Melo:
- Remove -fstack-clash-protection when building with some clang versions.
perf ordered_events:
Jiri Olsa:
- Fix out of buffers crash in ordered_events__free().
perf cpu_map:
Stephane Eranian:
- Handle TOPOLOGY headers with no CPU.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull btrfs fixes from David Sterba:
- regression fix: transaction commit can run away due to delayed ref
waiting heuristic, this is not necessary now because of the proper
reservation mechanism introduced in 5.0
- regression fix: potential crash due to use-before-check of an ERR_PTR
return value
- fix for transaction abort during transaction commit that needs to
properly clean up pending block groups
- fix deadlock during b-tree node/leaf splitting, when this happens on
some of the fundamental trees, we must prevent new tree block
allocation to re-enter indirectly via the block group flushing path
- potential memory leak after errors during mount
* tag 'for-5.0-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: On error always free subvol_name in btrfs_mount
btrfs: clean up pending block groups when transaction commit aborts
btrfs: fix potential oops in device_list_add
btrfs: don't end the transaction for delayed refs in throttle
Btrfs: fix deadlock when allocating tree block during leaf/node split
When reading 'efi_page_tables' debugfs triggers an out-of-bounds access here:
arch/arm64/mm/dump.c: 282
if (addr >= st->marker[1].start_address) {
called from:
arch/arm64/mm/dump.c: 331
note_page(st, addr, 2, pud_val(pud));
because st->marker++ is is called after "UEFI runtime end" which is the
last element in addr_marker[]. Therefore, add a terminator like the one
for kernel_page_tables, so it can be skipped to print out non-existent
markers.
Here's the KASAN bug report:
# cat /sys/kernel/debug/efi_page_tables
---[ UEFI runtime start ]---
0x0000000020000000-0x0000000020010000 64K PTE RW NX SHD AF ...
0x0000000020200000-0x0000000021340000 17664K PTE RW NX SHD AF ...
...
0x0000000021920000-0x0000000021950000 192K PTE RW x SHD AF ...
0x0000000021950000-0x00000000219a0000 320K PTE RW NX SHD AF ...
---[ UEFI runtime end ]---
---[ (null) ]---
---[ (null) ]---
BUG: KASAN: global-out-of-bounds in note_page+0x1f0/0xac0
Read of size 8 at addr ffff2000123f2ac0 by task read_all/42464
Call trace:
dump_backtrace+0x0/0x298
show_stack+0x24/0x30
dump_stack+0xb0/0xdc
print_address_description+0x64/0x2b0
kasan_report+0x150/0x1a4
__asan_report_load8_noabort+0x30/0x3c
note_page+0x1f0/0xac0
walk_pgd+0xb4/0x244
ptdump_walk_pgd+0xec/0x140
ptdump_show+0x40/0x50
seq_read+0x3f8/0xad0
full_proxy_read+0x9c/0xc0
__vfs_read+0xfc/0x4c8
vfs_read+0xec/0x208
ksys_read+0xd0/0x15c
__arm64_sys_read+0x84/0x94
el0_svc_handler+0x258/0x304
el0_svc+0x8/0xc
The buggy address belongs to the variable:
__compound_literal.0+0x20/0x800
Memory state around the buggy address:
ffff2000123f2980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff2000123f2a00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fa
>ffff2000123f2a80: fa fa fa fa 00 00 00 00 fa fa fa fa 00 00 00 00
^
ffff2000123f2b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff2000123f2b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0
[ ardb: fix up whitespace ]
[ mingo: fix up some moar ]
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Fixes: 9d80448ac92b ("efi/arm64: Add debugfs node to dump UEFI runtime page tables")
Link: http://lkml.kernel.org/r/20190202095017.13799-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull rdma fixes frfom Jason Gunthorpe:
"Not much so far. We have the usual batch of bugs and two fixes to code
merged this cycle:
- Restore valgrind support for the ioctl verbs interface merged this
window, and fix a missed error code on an error path from that
conversion
- A user reported crash on obsolete mthca hardware
- pvrdma was using the wrong command opcode toward the hypervisor
- NULL pointer crash regression when dumping rdma-cm over netlink
- Be conservative about exposing the global rkey"
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
RDMA/uverbs: Mark ioctl responses with UVERBS_ATTR_F_VALID_OUTPUT
RDMA/mthca: Clear QP objects during their allocation
RDMA/vmw_pvrdma: Return the correct opcode when creating WR
RDMA/cma: Add cm_id restrack resource based on kernel or user cm_id type
RDMA/nldev: Don't expose unsafe global rkey to regular user
RDMA/uverbs: Fix post send success return value in case of error
While updating perf to work with Python3 and Python2 I noticed that the
stat-cpi script was dumping core.
$ perf stat -e cycles,instructions record -o /tmp/perf.data /bin/false
Performance counter stats for '/bin/false':
802,148 cycles
604,622 instructions 802,148 cycles
604,622 instructions
0.001445842 seconds time elapsed
$ perf script -i /tmp/perf.data -s scripts/python/stat-cpi.py
Segmentation fault (core dumped)
...
...
rblist=rblist@entry=0xb2a200 <rt_stat>,
new_entry=new_entry@entry=0x7ffcb755c310) at util/rblist.c:33
ctx=<optimized out>, type=<optimized out>, create=<optimized out>,
cpu=<optimized out>, evsel=<optimized out>) at util/stat-shadow.c:118
ctx=<optimized out>, type=<optimized out>, st=<optimized out>)
at util/stat-shadow.c:196
count=count@entry=727442, cpu=cpu@entry=0, st=0xb2a200 <rt_stat>)
at util/stat-shadow.c:239
config=config@entry=0xafeb40 <stat_config>,
counter=counter@entry=0x133c6e0) at util/stat.c:372
...
...
The issue is that since 1fcd03946b52 perf_stat__update_shadow_stats now calls
update_runtime_stat passing rt_stat rather than calling update_stats but
perf_stat__init_shadow_stats has never been called to initialize rt_stat in
the script path processing recorded stat data.
Since I can't see any reason why perf_stat__init_shadow_stats() is presently
initialized like it is in builtin-script.c::perf_sample__fprint_metric()
[4bd1bef8bba2f] I'm proposing it instead be initialized once in __cmd_script
Committer testing:
After applying the patch:
# perf script -i /tmp/perf.data -s tools/perf/scripts/python/stat-cpi.py
0.001970: cpu -1, thread -1 -> cpi 1.709079 (1075684/629394)
#
No segfault.
Signed-off-by: Tony Jones <tonyj@suse.de>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Fixes: 1fcd03946b52 ("perf stat: Update per-thread shadow stats")
Link: http://lkml.kernel.org/r/20190120191414.12925-1-tonyj@suse.de
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull Devicetree fix from Rob Herring:
"A single fix for building DT bindings in-tree"
* tag 'devicetree-fixes-for-5.0-3' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
dt-bindings: Fix dt_binding_check target for in tree builds
The subvol_name is allocated in btrfs_parse_subvol_options and is
consumed and freed in mount_subvol. Add a free to the error paths that
don't call mount_subvol so that it is guaranteed that subvol_name is
freed when an error happens.
Fixes: 312c89fbca06 ("btrfs: cleanup btrfs_mount() using btrfs_mount_root()")
Cc: stable@vger.kernel.org # v4.19+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull xtensa fixes from Max Filippov:
- fix ccount_timer_shutdown for secondary CPUs
- fix secondary CPU initialization
- fix secondary CPU reset vector clash with double exception vector
- fix present CPUs when booting with 'maxcpus' parameter
- limit possible CPUs by configured NR_CPUS
- issue a warning if xtensa PIC is asked to retrigger anything other
than software IRQ
- fix masking/unmasking of the first two IRQs on xtensa MX PIC
- fix typo in Kconfig description for user space unaligned access
feature
- fix Kconfig warning for selecting BUILTIN_DTB
* tag 'xtensa-20190201' of git://github.com/jcmvbkbc/linux-xtensa:
xtensa: SMP: limit number of possible CPUs by NR_CPUS
xtensa: rename BUILTIN_DTB to BUILTIN_DTB_SOURCE
xtensa: Fix typo use space=>user space
drivers/irqchip: xtensa-mx: fix mask and unmask
drivers/irqchip: xtensa: add warning to irq_retrigger
xtensa: SMP: mark each possible CPU as present
xtensa: smp_lx200_defconfig: fix vectors clash
xtensa: SMP: fix secondary CPU initialization
xtensa: SMP: fix ccount_timer_shutdown
Pull drm fixes from Dave Airlie:
"The rc3 fixes are a bit scattered:
- meson, sun4i and rockchip all had missing of_node_put.
- qxl and virtio both were advertising dma-buf to userspace when they
really shouldn't have.
Otherwise:
meson:
- modesetting regression fix
i915 GVT:
- one cmd parser failure fix
- region cleanup fix in vGPU destroy
amdgpu:
- KFD fixes for arm64 mixed APU/DGPU
- vega12 powerplay fix
- raven DC fixes
- freesync fix"
* tag 'drm-fixes-2019-01-18' of git://anongit.freedesktop.org/drm/drm:
drm/amd/display: Detach backlight from stream
drm/sun4i: backend: add missing of_node_puts
Revert "drm/amdgpu: validate user pitch alignment"
Revert "drm/amdgpu: validate user GEM object size"
drm/meson: Fix atomic mode switching regression
drm/i915/gvt: Fix mmap range check
drm/i915/gvt: free VFIO region space in vgpu detach
drm/amd/display: Fix disabled cursor on top screen edge
drm/amd/display: fix warning on raven hotplug
drm/amd/display: fix PME notification not working in RV desktop
drm/amd/display: Only get the connector state for VRR when toggled
drm/amd/display: Pack DMCU iRAM alignment
drm/amd/powerplay: run acg btc for Vega12
drm/amdkfd: Don't assign dGPUs to APU topology devices
drm/amdkfd: Allow building KFD on ARM64 (v2)
drm/meson: add missing of_node_put
drm/virtio: drop prime import/export callbacks
drm/qxl: drop prime import/export callbacks
drm/i915/gvt: Allow F_CMD_ACCESS on mmio 0x21f0
drm/rockchip: add missing of_node_put
When the ioctl interface for the write commands was introduced it did
not mark the core response with UVERBS_ATTR_F_VALID_OUTPUT. This causes
rdma-core in userspace to not mark the buffers as written for valgrind.
Along the same lines it turns out we have always missed marking the driver
data. Fixing both of these makes valgrind work properly with rdma-core and
ioctl.
Fixes: 4785860e04bc ("RDMA/uverbs: Implement an ioctl that can call write and write_ex handlers")
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
The annotation line percentage is compared and inserted into the rbtree,
but the percent field of 'struct annotation_data' is an array, the
comparison result between them is the address difference.
This patch compares the right slot of percent array according to
opts->percent_type and makes things right.
The problem can be reproduced by pressing 'H' in perf top annotation view.
It should highlight the instruction line which has the highest sampling
percentage.
Signed-off-by: He Kuang <hekuang@huawei.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190120160523.4391-1-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull RISC-V fixes from Palmer Dabbelt:
"This contains a handful of mostly-independent patches:
- make our port respect TIF_NEED_RESCHED, which fixes
CONFIG_PREEMPT=y kernels
- fix double-put of OF nodes
- fix a misspelling of target in our Kconfig
- generic PCIe is enabled in our defconfig
- fix our SBI early console to properly handle line
endings
- fix max_low_pfn being counted in PFNs
- a change to TASK_UNMAPPED_BASE to match what other
arches do
This has passed my standard 'boot Fedora' flow"
* tag 'riscv-for-linus-5.0-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux:
riscv: Adjust mmap base address at a third of task size
riscv: fixup max_low_pfn with PFN_DOWN.
tty/serial: use uart_console_write in the RISC-V SBL early console
RISC-V: defconfig: Add CRYPTO_DEV_VIRTIO=y
RISC-V: defconfig: Enable Generic PCIE by default
RISC-V: defconfig: Move CONFIG_PCI{,E_XILINX}
RISC-V: Kconfig: fix spelling mistake "traget" -> "target"
RISC-V: asm/page.h: fix spelling mistake "CONFIG_64BITS" -> "CONFIG_64BIT"
RISC-V: fix bad use of of_node_put
RISC-V: Add _TIF_NEED_RESCHED check for kernel thread when CONFIG_PREEMPT=y
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