Re: [PATCH AUTOSEL 5.17 31/66] printk: Add panic_in_progress helper

[Sasha Levin <sashal@kernel.org>]

On Wed, Mar 30, 2022 at 01:51:08PM +0200, Greg KH wrote:
>On Wed, Mar 30, 2022 at 07:46:10AM -0400, Sasha Levin wrote:
>> From: Stephen Brennan <stephen.s.brennan@oracle.com>
>>
>> [ Upstream commit 77498617857f68496b360081dde1a492d40c28b2 ]
>>
>> This will be used help avoid deadlocks during panics. Although it would
>> be better to include this in linux/panic.h, it would require that header
>> to include linux/atomic.h as well. On some architectures, this results
>> in a circular dependency as well. So instead add the helper directly to
>> printk.c.
>>
>> Suggested-by: Petr Mladek <pmladek@suse.com>
>> Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
>> Reviewed-by: Petr Mladek <pmladek@suse.com>
>> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
>> Signed-off-by: Petr Mladek <pmladek@suse.com>
>> Link: https://lore.kernel.org/r/20220202171821.179394-2-stephen.s.brennan@oracle.com
>> Signed-off-by: Sasha Levin <sashal@kernel.org>
>> ---
>>  kernel/printk/printk.c | 5 +++++
>>  1 file changed, 5 insertions(+)
>>
>> diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
>> index 82abfaf3c2aa..0f8918f5f22a 100644
>> --- a/kernel/printk/printk.c
>> +++ b/kernel/printk/printk.c
>> @@ -257,6 +257,11 @@ static void __up_console_sem(unsigned long ip)
>>  }
>>  #define up_console_sem() __up_console_sem(_RET_IP_)
>>
>> +static bool panic_in_progress(void)
>> +{
>> +	return unlikely(atomic_read(&panic_cpu) != PANIC_CPU_INVALID);
>> +}
>> +
>>  /*
>>   * This is used for debugging the mess that is the VT code by
>>   * keeping track if we have the console semaphore held. It's
>> --
>> 2.34.1
>>
>
>All 4 of the printk patches should not need to be backported to stable
>kernels, thanks.  Please drop them all.

I'll drop them, thanks.

-- 
Thanks,
Sasha