On Thu, 22 Jul 2021 21:22:58 +0200I would add:
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:
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.
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
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.
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
Signed-off-by: Halil Pasic <pasic@xxxxxxxxxxxxx>
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
@@ -186,9 +186,9 @@ static void pv_init(void)
/* make sure bounce buffers are shared */
+ swiotlb_force = SWIOTLB_FORCE;
- swiotlb_force = SWIOTLB_FORCE;
void __init mem_init(void)