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Yang Jihong 37a65df6a9 perf/core: Fix reentry problem in perf_output_read_group()
commit 6b959ba22d upstream.

perf_output_read_group may respond to IPI request of other cores and invoke
__perf_install_in_context function. As a result, hwc configuration is modified.
causing inconsistency and unexpected consequences.

Interrupts are not disabled when perf_output_read_group reads PMU counter.
In this case, IPI request may be received from other cores.
As a result, PMU configuration is modified and an error occurs when
reading PMU counter:

		     CPU0                                         CPU1
						      __se_sys_perf_event_open
							perf_install_in_context
  perf_output_read_group                                  smp_call_function_single
    for_each_sibling_event(sub, leader) {                   generic_exec_single
      if ((sub != event) &&                                   remote_function
	  (sub->state == PERF_EVENT_STATE_ACTIVE))                    |
  <enter IPI handler: __perf_install_in_context>   <----RAISE IPI-----+
  __perf_install_in_context
    ctx_resched
      event_sched_out
	armpmu_del
	  ...
	  hwc->idx = -1; // event->hwc.idx is set to -1
  ...
  <exit IPI>
	      sub->pmu->read(sub);
		armpmu_read
		  armv8pmu_read_counter
		    armv8pmu_read_hw_counter
		      int idx = event->hw.idx; // idx = -1
		      u64 val = armv8pmu_read_evcntr(idx);
			u32 counter = ARMV8_IDX_TO_COUNTER(idx); // invalid counter = 30
			read_pmevcntrn(counter) // undefined instruction

Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20220902082918.179248-1-yangjihong1@huawei.com
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@igalia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-13 12:51:30 +02:00
arch x86/speculation: Support intra-function call validation 2024-04-13 12:51:29 +02:00
block block: sed-opal: handle empty atoms when parsing response 2024-03-26 18:22:12 -04:00
certs certs/blacklist_hashes.c: fix const confusion in certs blacklist 2022-06-22 14:11:22 +02:00
crypto crypto: api - Disallow identical driver names 2024-02-23 08:24:48 +01:00
Documentation x86/cpu: Support AMD Automatic IBRS 2024-04-13 12:51:21 +02:00
drivers loop: loop_set_status_from_info() check before assignment 2024-04-13 12:51:30 +02:00
fs btrfs: allocate btrfs_ioctl_defrag_range_args on stack 2024-04-13 12:51:30 +02:00
include objtool: Add support for intra-function calls 2024-04-13 12:51:29 +02:00
init rootfs: Fix support for rootfstype= when root= is given 2024-01-25 14:34:30 -08:00
ipc ipc/sem: Fix dangling sem_array access in semtimedop race 2022-12-08 11:23:06 +01:00
kernel perf/core: Fix reentry problem in perf_output_read_group() 2024-04-13 12:51:30 +02:00
lib net: blackhole_dev: fix build warning for ethh set but not used 2024-03-26 18:22:15 -04:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm memtest: use {READ,WRITE}_ONCE in memory scanning 2024-04-13 12:51:27 +02:00
net xfrm: Avoid clang fortify warning in copy_to_user_tmpl() 2024-04-13 12:51:28 +02:00
samples media: rename VFL_TYPE_GRABBER to _VIDEO 2024-03-26 18:22:22 -04:00
scripts kbuild: Move -Wenum-{compare-conditional,enum-conversion} into W=1 2024-04-13 12:51:26 +02:00
security smack: Handle SMACK64TRANSMUTE in smack_inode_setsecurity() 2024-04-13 12:51:22 +02:00
sound ALSA: hda/realtek - Fix headset Mic no show at resume back for Lenovo ALC897 platform 2024-04-13 12:51:28 +02:00
tools objtool: Add support for intra-function calls 2024-04-13 12:51:29 +02:00
usr initramfs: restore default compression behavior 2020-04-08 09:08:38 +02:00
virt KVM: Always flush async #PF workqueue when vCPU is being destroyed 2024-04-13 12:51:22 +02:00
.clang-format clang-format: Update with the latest for_each macro list 2019-08-31 10:00:51 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes
.gitignore Modules updates for v5.4 2019-09-22 10:34:46 -07:00
.mailmap ARM: SoC fixes 2019-11-10 13:41:59 -08:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS MAINTAINERS: Remove Simon as Renesas SoC Co-Maintainer 2019-10-10 08:12:51 -07:00
Kbuild kbuild: do not descend to ./Kbuild when cleaning 2019-08-21 21:03:58 +09:00
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
MAINTAINERS iio: stx104: Move to addac subdirectory 2023-08-30 16:27:12 +02:00
Makefile Linux 5.4.273 2024-03-26 18:23:12 -04:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

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.