Re: git-bisect points to block: discard granularity might not bepower of 2

From: Jens Axboe
Date: Thu Dec 20 2012 - 08:41:03 EST

On 2012-12-20 14:33, Arthur Marsh wrote:
> Hi,
> one of my machines is locking up fairly early in the boot process (about 1.4 seconds in) with recent kernels and a git-bisect lead to:
> commit 8dd2cb7e880d2f77fba53b523c99133ad5054cfd
> Author: Shaohua Li <shli@xxxxxxxxxx>
> Date: Fri Dec 14 11:15:36 2012 +0800
> block: discard granularity might not be power of 2
> In MD raid case, discard granularity might not be power of 2, for example, a
> 4-disk raid5 has 3*chunk_size discard granularity. Correct the calculation for
> such cases.
> Reported-by: Neil Brown <neilb@xxxxxxx>
> Signed-off-by: Shaohua Li <shli@xxxxxxxxxxxx>
> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
> The machine is a dual core Pentium IV with 2 IDE and one SCSI disk. I've tried pulling the SCSI card out and the problem still occurs.
> There are no software raid arrays assembled in the boot process.
> Short of taking a photo of the monitor with the dump on it I'm a bit stuck as to what to do to further identify the problem.

Should be fixed in Linus' tree as-of yesterday. So please try that and
report back if it doesn't work.

Jens Axboe

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