Re: [PATCH 1/2] MIPS: Disable preemption during prctl(PR_SET_FP_MODE, ...)

From: Aurelien Jarno
Date: Tue May 10 2016 - 16:15:49 EST


On 2016-04-21 12:43, Paul Burton wrote:
> Whilst a PR_SET_FP_MODE prctl is performed there are decisions made
> based upon whether the task is executing on the current CPU. This may
> change if we're preempted, so disable preemption to avoid such changes
> for the lifetime of the mode switch.
>
> Signed-off-by: Paul Burton <paul.burton@xxxxxxxxxx>
> Fixes: 9791554b45a2 ("MIPS,prctl: add PR_[GS]ET_FP_MODE prctl options for MIPS")
> Cc: stable <stable@xxxxxxxxxxxxxxx> # v4.0+
> ---
>
> arch/mips/kernel/process.c | 4 ++++
> 1 file changed, 4 insertions(+)

Both patches fixes building pillow, which otherwise hangs running
"python setup.py build" [1]. The setup code uses the multiprocessing
package, and it hangs in a call to PR_SET_FP_MODE.

You can therefore add for both patches:

Tested-by: Aurelien Jarno <aurelien@xxxxxxxxxxx>

Thanks,
Aurelien

[1] https://buildd.debian.org/status/fetch.php?pkg=pillow&arch=mips&ver=3.2.0-1&stamp=1460852908

--
Aurelien Jarno GPG: 4096R/1DDD8C9B
aurelien@xxxxxxxxxxx http://www.aurel32.net