On Fri, Jul 23, 2021 at 10:50:57AM +0200, Christian Borntraeger wrote: > > > On 23.07.21 10:47, Halil Pasic wrote: > > On Fri, 23 Jul 2021 08:14:19 +0200 > > Christian Borntraeger <borntraeger@xxxxxxxxxx> wrote: > > > > > Resending with the correct email of Heiko.... > > > > > > On 23.07.21 03:12, Halil Pasic wrote: > > > > On Thu, 22 Jul 2021 21:22:58 +0200 > > > > Christian Borntraeger <borntraeger@xxxxxxxxxx> wrote: > > > > > On 20.07.21 15:38, Will Deacon wrote: > > > > > > Hi again, folks, > > > > > > > > > > > > This is version two of the patch series I posted yesterday: > > > > > > > > > > > > https://lore.kernel.org/r/20210719123054.6844-1-will@xxxxxxxxxx > > > > > > > > > > > > The only changes since v1 are: > > > > > > > > > > > > * Squash patches 2 and 3, amending the commit message accordingly > > > > > > * Add Reviewed-by and Tested-by tags from Christoph and Claire (thanks!) > > > > > > > > > > > > I'd usually leave it a bit longer between postings, but since this fixes > > > > > > issues with patches in -next I thought I'd spin a new version immediately. > > > > > > > > > > > > Cheers, > > > > > > > > > > FWIW, I just bisected virtio-errors with secure execution mode > > > > > qemu-system-s390x: virtio-serial-bus: Unexpected port id 4205794771 for device virtio-serial0.0 > > > > > > > > > > to > > > > > commit 903cd0f315fe426c6a64c54ed389de0becb663dc > > > > > Author: Claire Chang <tientzu@xxxxxxxxxxxx> > > > > > Date: Thu Jun 24 23:55:20 2021 +0800 > > > > > > > > > > swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing > > > > > > > > > > Unfortunately this patch series does NOT fix this issue, so it seems that even more > > > > > things are broken. > > > > > > > > > > Any idea what else might be broken? > > > > > > > > I've done some debugging, and I think I know what is going on. Since > > > > that commit we need to set force_swiotlb before the swiotlb itself is > > > > initialized. So the patch below should fix the problem. > > > > > > > > --------------------8<------------------------------------- > > > > > > > > From: Halil Pasic <pasic@xxxxxxxxxxxxx> > > > > Date: Fri, 23 Jul 2021 02:57:06 +0200 > > > > Subject: [PATCH 1/1] s390/pv: fix the forcing of the swiotlb > > > > > > > > Since commit 903cd0f315fe ("swiotlb: Use is_swiotlb_force_bounce for > > > > swiotlb data bouncing") if code sets swiotlb_force it needs to do so > > > > before the swiotlb is initialised. Otherwise > > > > io_tlb_default_mem->force_bounce will not get set to true, and devices > > > > that use (the default) swiotlb will not bounce despite switolb_force > > > > having the value of SWIOTLB_FORCE. > > > > > > > > Let us restore swiotlb functionality for PV by fulfilling this new > > > > requirement. > > > I would add: > > > Fixes: 903cd0f315fe ("swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing") > > > as this patch breaks things > > > and > > > Fixes: 64e1f0c531d1 ("s390/mm: force swiotlb for protected virtualization") > > > > > > to make the s390 init code more robust in case people start backporting things. > > > > I agree. Do we want this backported to the stable releases that have > > 64e1f0c531d1 (i.e. do we need a cc stable) or should the fixes tag just > > serve as metadata? My guess is, it's the former. In that sense should I > > add the tags along with an explanation for the second fixes respin with > > cc stable? > > > > (BTW I don't think this formally qualifies for the stable backports, but > > I hope we can make an exception...) > > I think it makes sense for stable as it is cleaner to set the flags before > calling the init function. cc stable would be better and the right way > according to process, but the Fixes tag is mostly enough. But the reaso for fixing this is for code that is not yet in Linus's tree? I can just pick this patch up and add it in the pile I have for the next merge window? > > > > > > > > > > Signed-off-by: Halil Pasic <pasic@xxxxxxxxxxxxx> > > > > > > I can confirm that this fixes the problem. This also makes sense codewise. > > > > > > Tested-by: Christian Borntraeger <borntraeger@xxxxxxxxxx> > > > Reviewed-by: Christian Borntraeger <borntraeger@xxxxxxxxxx> > > > > Thanks! > > > > Regards, > > Halil > > > > > > Konrad, Heiko, Vasily, any preference which tree this goes? I think s390 > > > would be easiest, but that requires that the patches in the swiotlb tree have > > > fixed commit IDs. > > > > > > > --- > > > > arch/s390/mm/init.c | 2 +- > > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > > > diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c > > > > index 8ac710de1ab1..07bbee9b7320 100644 > > > > --- a/arch/s390/mm/init.c > > > > +++ b/arch/s390/mm/init.c > > > > @@ -186,9 +186,9 @@ static void pv_init(void) > > > > return; > > > > /* make sure bounce buffers are shared */ > > > > + swiotlb_force = SWIOTLB_FORCE; > > > > swiotlb_init(1); > > > > swiotlb_update_mem_attributes(); > > > > - swiotlb_force = SWIOTLB_FORCE; > > > > } > > > > void __init mem_init(void) > >
