Linux kernel
============
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In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
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.
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Pull perf tools fixes from Arnaldo Carvalho de Melo:
- BPF program info linear (BPIL) data is accessed assuming 64-bit
alignment resulting in undefined behavior as the data is just byte
aligned. Fix it, Found using -fsanitize=undefined.
- Fix 'perf offcpu' build on old kernels wrt task_struct's
state/__state field.
- Fix perf_event_attr.sample_type setting on the 'offcpu-time' event
synthesized by the 'perf offcpu' tool.
- Don't bail out when synthesizing PERF_RECORD_ events for pre-existing
threads when one goes away while parsing its procfs entries.
- Don't sort the task scan result from /proc, its not needed and
introduces bugs when the main thread isn't the first one to be
processed.
- Fix uninitialized 'offset' variable on aarch64 in the unwind code.
- Sync KVM headers with the kernel sources.
* tag 'perf-tools-fixes-for-v5.19-2022-07-02' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
perf synthetic-events: Ignore dead threads during event synthesis
perf synthetic-events: Don't sort the task scan result from /proc
perf unwind: Fix unitialized 'offset' variable on aarch64
tools headers UAPI: Sync linux/kvm.h with the kernel sources
perf bpf: 8 byte align bpil data
tools kvm headers arm64: Update KVM headers from the kernel sources
perf offcpu: Accept allowed sample types only
perf offcpu: Fix build failure on old kernels
Pull powerpc fixes from Michael Ellerman:
- Fix BPF uapi confusion about the correct type of bpf_user_pt_regs_t.
- Fix virt_addr_valid() when memory is hotplugged above the boot-time
high_memory value.
- Fix a bug in 64-bit Book3E map_kernel_page() which would incorrectly
allocate a PMD page at PUD level.
- Fix a couple of minor issues found since we enabled KASAN for 64-bit
Book3S.
Thanks to Aneesh Kumar K.V, Cédric Le Goater, Christophe Leroy, Kefeng
Wang, Liam Howlett, Nathan Lynch, and Naveen N. Rao.
* tag 'powerpc-5.19-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/memhotplug: Add add_pages override for PPC
powerpc/bpf: Fix use of user_pt_regs in uapi
powerpc/prom_init: Fix kernel config grep
powerpc/book3e: Fix PUD allocation size in map_kernel_page()
powerpc/xive/spapr: correct bitmap allocation size
When it synthesize various task events, it scans the list of task
first and then accesses later. There's a window threads can die
between the two and proc entries may not be available.
Instead of bailing out, we can ignore that thread and move on.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20220701205458.985106-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull libnvdimm fix from Vishal Verma:
- Fix a bug in the libnvdimm 'BTT' (Block Translation Table) driver
where accounting for poison blocks to be cleared was off by one,
causing a failure to clear the the last badblock in an nvdimm region.
* tag 'libnvdimm-fixes-5.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
nvdimm: Fix badblocks clear off-by-one error
With commit ffa0b64e3be5 ("powerpc: Fix virt_addr_valid() for 64-bit Book3E & 32-bit")
the kernel now validate the addr against high_memory value. This results
in the below BUG_ON with dax pfns.
[ 635.798741][T26531] kernel BUG at mm/page_alloc.c:5521!
1:mon> e
cpu 0x1: Vector: 700 (Program Check) at [c000000007287630]
pc: c00000000055ed48: free_pages.part.0+0x48/0x110
lr: c00000000053ca70: tlb_finish_mmu+0x80/0xd0
sp: c0000000072878d0
msr: 800000000282b033
current = 0xc00000000afabe00
paca = 0xc00000037ffff300 irqmask: 0x03 irq_happened: 0x05
pid = 26531, comm = 50-landscape-sy
kernel BUG at :5521!
Linux version 5.19.0-rc3-14659-g4ec05be7c2e1 (kvaneesh@ltc-boston8) (gcc (Ubuntu 9.4.0-1ubuntu1~20.04.1) 9.4.0, GNU ld (GNU Binutils for Ubuntu) 2.34) #625 SMP Thu Jun 23 00:35:43 CDT 2022
1:mon> t
[link register ] c00000000053ca70 tlb_finish_mmu+0x80/0xd0
[c0000000072878d0] c00000000053ca54 tlb_finish_mmu+0x64/0xd0 (unreliable)
[c000000007287900] c000000000539424 exit_mmap+0xe4/0x2a0
[c0000000072879e0] c00000000019fc1c mmput+0xcc/0x210
[c000000007287a20] c000000000629230 begin_new_exec+0x5e0/0xf40
[c000000007287ae0] c00000000070b3cc load_elf_binary+0x3ac/0x1e00
[c000000007287c10] c000000000627af0 bprm_execve+0x3b0/0xaf0
[c000000007287cd0] c000000000628414 do_execveat_common.isra.0+0x1e4/0x310
[c000000007287d80] c00000000062858c sys_execve+0x4c/0x60
[c000000007287db0] c00000000002c1b0 system_call_exception+0x160/0x2c0
[c000000007287e10] c00000000000c53c system_call_common+0xec/0x250
The fix is to make sure we update high_memory on memory hotplug.
This is similar to what x86 does in commit 3072e413e305 ("mm/memory_hotplug: introduce add_pages")
Fixes: ffa0b64e3be5 ("powerpc: Fix virt_addr_valid() for 64-bit Book3E & 32-bit")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220629050925.31447-1-aneesh.kumar@linux.ibm.com
It should not sort the result as procfs already returns a proper
ordering of tasks. Actually sorting the order caused problems that it
doesn't guararantee to process the main thread first.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20220701205458.985106-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull thermal control fix from Rafael Wysocki:
"Add a new CPU ID to the list of supported processors in the
intel_tcc_cooling driver (Sumeet Pawnikar)"
* tag 'thermal-5.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
thermal: intel_tcc_cooling: Add TCC cooling support for RaptorLake
nvdimm_clear_badblocks_region() validates badblock clearing requests
against the span of the region, however it compares the inclusive
badblock request range to the exclusive region range. Fix up the
off-by-one error.
Fixes: 23f498448362 ("libnvdimm: rework region badblocks clearing")
Cc: <stable@vger.kernel.org>
Signed-off-by: Chris Ye <chris.ye@intel.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Link: https://lore.kernel.org/r/165404219489.2445897.9792886413715690399.stgit@dwillia2-xfh
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Trying to build a .c file that includes <linux/bpf_perf_event.h>:
$ cat test_bpf_headers.c
#include <linux/bpf_perf_event.h>
throws the below error:
/usr/include/linux/bpf_perf_event.h:14:28: error: field ‘regs’ has incomplete type
14 | bpf_user_pt_regs_t regs;
| ^~~~
This is because we typedef bpf_user_pt_regs_t to 'struct user_pt_regs'
in arch/powerpc/include/uaps/asm/bpf_perf_event.h, but 'struct
user_pt_regs' is not exposed to userspace.
Powerpc has both pt_regs and user_pt_regs structures. However, unlike
arm64 and s390, we expose user_pt_regs to userspace as just 'pt_regs'.
As such, we should typedef bpf_user_pt_regs_t to 'struct pt_regs' for
userspace.
Within the kernel though, we want to typedef bpf_user_pt_regs_t to
'struct user_pt_regs'.
Remove arch/powerpc/include/uapi/asm/bpf_perf_event.h so that the
uapi/asm-generic version of the header is exposed to userspace.
Introduce arch/powerpc/include/asm/bpf_perf_event.h so that we can
typedef bpf_user_pt_regs_t to 'struct user_pt_regs' for use within the
kernel.
Note that this was not showing up with the bpf selftest build since
tools/include/uapi/asm/bpf_perf_event.h didn't include the powerpc
variant.
Fixes: a6460b03f945ee ("powerpc/bpf: Fix broken uapi for BPF_PROG_TYPE_PERF_EVENT")
Cc: stable@vger.kernel.org # v4.20+
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
[mpe: Use typical naming for header include guard]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220627191119.142867-1-naveen.n.rao@linux.vnet.ibm.com
Commit dc2cf4ca866f5715 ("perf unwind: Fix segbase for ld.lld linked
objects") uncovered the following issue on aarch64:
util/unwind-libunwind-local.c: In function 'find_proc_info':
util/unwind-libunwind-local.c:386:28: error: 'offset' may be used uninitialized in this function [-Werror=maybe-uninitialized]
386 | if (ofs > 0) {
| ^
util/unwind-libunwind-local.c:199:22: note: 'offset' was declared here
199 | u64 address, offset;
| ^~~~~~
util/unwind-libunwind-local.c:371:20: error: 'offset' may be used uninitialized in this function [-Werror=maybe-uninitialized]
371 | if (ofs <= 0) {
| ^
util/unwind-libunwind-local.c:199:22: note: 'offset' was declared here
199 | u64 address, offset;
| ^~~~~~
util/unwind-libunwind-local.c:363:20: error: 'offset' may be used uninitialized in this function [-Werror=maybe-uninitialized]
363 | if (ofs <= 0) {
| ^
util/unwind-libunwind-local.c:199:22: note: 'offset' was declared here
199 | u64 address, offset;
| ^~~~~~
In file included from util/libunwind/arm64.c:37:
Fixes: dc2cf4ca866f5715 ("perf unwind: Fix segbase for ld.lld linked objects")
Signed-off-by: Ivan Babrou <ivan@cloudflare.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Fangrui Song <maskray@google.com>
Cc: Ian Rogers <irogers@google.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: kernel-team@cloudflare.com
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20220701182046.12589-1-ivan@cloudflare.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull power management fixes from Rafael Wysocki:
"These fix some issues in cpufreq drivers and some issues in devfreq:
- Fix error code path issues related PROBE_DEFER handling in devfreq
(Christian Marangi)
- Revert an editing accident in SPDX-License line in the devfreq
passive governor (Lukas Bulwahn)
- Fix refcount leak in of_get_devfreq_events() in the exynos-ppmu
devfreq driver (Miaoqian Lin)
- Use HZ_PER_KHZ macro in the passive devfreq governor (Yicong Yang)
- Fix missing of_node_put for qoriq and pmac32 driver (Liang He)
- Fix issues around throttle interrupt for qcom driver (Stephen Boyd)
- Add MT8186 to cpufreq-dt-platdev blocklist (AngeloGioacchino Del
Regno)
- Make amd-pstate enable CPPC on resume from S3 (Jinzhou Su)"
* tag 'pm-5.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / devfreq: passive: revert an editing accident in SPDX-License line
PM / devfreq: Fix kernel warning with cpufreq passive register fail
PM / devfreq: Rework freq_table to be local to devfreq struct
PM / devfreq: exynos-ppmu: Fix refcount leak in of_get_devfreq_events
PM / devfreq: passive: Use HZ_PER_KHZ macro in units.h
PM / devfreq: Fix cpufreq passive unregister erroring on PROBE_DEFER
PM / devfreq: Mute warning on governor PROBE_DEFER
PM / devfreq: Fix kernel panic with cpu based scaling to passive gov
cpufreq: Add MT8186 to cpufreq-dt-platdev blocklist
cpufreq: pmac32-cpufreq: Fix refcount leak bug
cpufreq: qcom-hw: Don't do lmh things without a throttle interrupt
drivers: cpufreq: Add missing of_node_put() in qoriq-cpufreq.c
cpufreq: amd-pstate: Add resume and suspend callbacks
Add RaptorLake to the list of processor models supported by the Intel
TCC cooling driver.
Signed-off-by: Sumeet Pawnikar <sumeet.r.pawnikar@intel.com>
[ rjw: Subject edits, new changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>