On Thu, 2018-03-15 at 16:28 +0100, Joerg Roedel wrote: > On Thu, Mar 15, 2018 at 02:42:00PM +0000, Dmitry Safonov wrote: > > But even with loop-limit we will need ratelimit each printk() > > *also*. > > Otherwise loop-limit will be based on time spent printing, not on > > anything else.. > > The patch makes sense even with loop-limit in my opinion. > > Looks like I mis-read your patch, somehow it looked to me as if you > replace all 'ratelimited' usages with a call to __ratelimit(), but > you > just move 'ratelimited' into the loop, which actually makes sense.
So, is it worth to apply the patch? > But still, this alone is no proper fix for the soft-lockups you are > seeing. Hmm, but this fixes my softlockup issue, because it's about time spent in printk() inside irq-disabled section, rather about exiting the dmar- clearing loop. And on my hw doesn't make any difference to limit loop or not because clearing a fault is much faster than hw could generate a new fault. ITOW, it fixes the softlockup for me and the loop-related lockup can't happen on hw I have (so it's the other issue, [possible?] on other hw). -- Thanks, Dmitry _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu