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charset=us-ascii Content-Disposition: inline In-Reply-To: <20240812072703.339690-1-takakura@valinux.co.jp> On Mon 2024-08-12 16:27:03, takakura@valinux.co.jp wrote: > From: Ryo Takakura > > commit 779dbc2e78d7 ("printk: Avoid non-panic CPUs writing > to ringbuffer") disabled non-panic CPUs to further write messages to > ringbuffer after panicked. > > Since the commit, non-panicked CPU's are not allowed to write to > ring buffer after panicked and CPU backtrace which is triggered > after panicked to sample non-panicked CPUs' backtrace no longer > serves its function as it has nothing to print. > > Fix the issue by allowing non-panicked CPUs to write into ringbuffer > while CPU backtrace is in flight. > > Fixes: 779dbc2e78d7 ("printk: Avoid non-panic CPUs writing to ringbuffer") > Signed-off-by: Ryo Takakura > Reviewed-by: Petr Mladek JFYI, I have pushed this patch into printk/linux.git, branch for-6.11-fixup. I am going to create pull request after it spends at least one or two days in linux-next. The 2nd patch is more complicated. It depends on another patchset integrating con->write_atomic() callback. Best Regards, Petr