mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

xtensa: patch_text: Fixup last cpu should be master 

These patch_text implementations are using stop_machine_cpuslocked
infrastructure with atomic cpu_count. The original idea: When the
master CPU patch_text, the others should wait for it. But current
implementation is using the first CPU as master, which couldn't
guarantee the remaining CPUs are waiting. This patch changes the
last CPU as the master to solve the potential risk.

Fixes: 64711f9a47 ("xtensa: implement jump_label support")
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: <stable@vger.kernel.org>
Message-Id: <20220407073323.743224-4-guoren@kernel.org>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
This commit is contained in:
Guo Ren 2022-04-07 15:33:22 +08:00 committed by Max Filippov
parent ce522ba9ef
commit ee69d4be8f
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/xtensa/kernel/jump_label.c
View File

@ -40,7 +40,7 @@ static int patch_text_stop_machine(void *data)
{
struct patch *patch = data;
if (atomic_inc_return(&patch->cpu_count) == 1) {
if (atomic_inc_return(&patch->cpu_count) == num_online_cpus()) {
local_patch_text(patch->addr, patch->data, patch->sz);
atomic_inc(&patch->cpu_count);
} else {