Re: Commit ab6f762f0f5 ("printk: queue wake_up_klogd irq_work only if per-CPU areas are ready") for v5.4.y/v5.6.y

On Wed, Apr 29, 2020 at 09:25:10AM -0700, Guenter Roeck wrote:

Hi,

commit ab6f762f0f53 ("printk: queue wake_up_klogd irq_work only if per-CPU areas are ready") fixes a critical problem introduced with commit 1b710b1b10ef ("char/random: silence a lockdep splat with printk()"). Since commit 1b710b1b10ef has been applied to v5.4.y, commit ab6f762f0f53 needs to be applied as well.

An alternative might be to revert commit 1b710b1b10ef from v5.4.y, as it was done for older kernel branches. However, we found that ab6f762f0f53 applies cleanly to v5.4.y and fixes the problem, so applying the fix is probably a better solution.

Commit ab6f762f0f53 also needs to be applied to v5.6.y.

I have applied it to 5.4.y and 5.6.y now, thanks.

greg k-h