Re: [PATCH v4] hwrng: core - Stop/start hwrng_fillfn() kthread before/after suspend-resume

[Herbert Xu]

On Mon, Jul 13, 2026 at 01:25:37PM +0200, Thomas Richard (TI) wrote:
>
> This is the fourth iteration, as requested by Herbert I replaced BUG_ON()
> by lockdep_assert_held().
> ---
> Changes in v4:
> - use lockdep_assert_held() instead of BUG_ON()
> - Link to v3: https://lore.kernel.org/r/20260703-hw-random-fix-hwrng-fillfn-crash-suspend-resume-v3-1-b7165cb9cf38@xxxxxxxxxxx

https://sashiko.dev/#/patchset/20260713-hw-random-fix-hwrng-fillfn-crash-suspend-resume-v4-1-b5fb4c520b05%40bootlin.com

Sashiko is asking about whether user-space can restart the hwrng
thread via sysfs after you stop it in the notifier.  I know nothing
about suspension so I can't say whether that's possible.  But if
it is possible then you'd need to close the race window with a flag
of some kind.

Thanks,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt