Hi Max,
On 23.09.2024 00:47, Max Gurtovoy wrote:
>
> On 17/09/2024 17:09, Marek Szyprowski wrote:
>> On 17.09.2024 00:06, Max Gurtovoy wrote:
>>> On 12/09/2024 9:46, Marek Szyprowski wrote:
>>>> Dear All,
>>>>
>>>> On 08.08.2024 00:41, Max Gurtovoy wrote:
>>>>> Set the driver data of the hardware context (hctx) to point
>>>>> directly to
>>>>> the virtio block queue. This cleanup improves code readability and
>>>>> reduces the number of dereferences in the fast path.
>>>>>
>>>>> Reviewed-by: Stefan Hajnoczi <stefanha@xxxxxxxxxx>
>>>>> Signed-off-by: Max Gurtovoy <mgurtovoy@xxxxxxxxxx>
>>>>> ---
>>>>> drivers/block/virtio_blk.c | 42
>>>>> ++++++++++++++++++++------------------
>>>>> 1 file changed, 22 insertions(+), 20 deletions(-)
>>>> This patch landed in recent linux-next as commit 8d04556131c1
>>>> ("virtio_blk: implement init_hctx MQ operation"). In my tests I found
>>>> that it introduces a regression in system suspend/resume operation.
>>>> From
>>>> time to time system crashes during suspend/resume cycle. Reverting
>>>> this
>>>> patch on top of next-20240911 fixes this problem.
>>> Could you please provide a detailed explanation of the system
>>> suspend/resume operation and the specific testing methodology employed?
>> In my tests I just call the 'rtcwake -s10 -mmem' command many times in a
>> loop. I use standard Debian image under QEMU/ARM64. Nothing really
>> special.
>
> I run this test on my bare metal x86 server in a loop with fio in the
> background.
>
> The test passed.
Maybe QEMU is a bit slower and exposes some kind of race caused by this
change.
>
> Can you please re-test with the linux/master branch with applying this
> patch on top ?
This issue is fully reproducible with vanilla v6.11 and v6.10 from Linus
and $subject patch applied on top of it.
I've even checked it with x86_64 QEMU and first random Debian
preinstalled image I've found.
Here is a detailed setup if You like to check it by yourself (tested on
Ubuntu 22.04 LTS x86_64 host):
1. download x86_64 preinstalled Debian image:
# wget
https://dietpi.com/downloads/images/DietPi_NativePC-BIOS-x86_64-Bookworm.img.xz
# xz -d DietPi_NativePC-BIOS-x86_64-Bookworm.img.xz
2. build kernel:
# make x86_64_defconfig
# make -j12
3. run QEMU:
# sudo qemu-system-x86_64 -enable-kvm \
-kernel PATH_TO_YOUR_KERNEL_DIR/arch/x86/boot/bzImage \
-append "console=ttyS0 root=/dev/vda1 rootwait noapic tsc=unstable
init=/bin/sh" \
-smp 2 -m 2048 \
-drive
file=DietPi_NativePC-BIOS-x86_64-Bookworm.img,format=raw,if=virtio \
-netdev user,id=net0 -device virtio-net,netdev=net0 \
-serial mon:stdio -nographic
4. let it boot, then type (copy&paste line by line) in the init shell:
# mount proc /proc -t proc
# mount sys /sys -t sysfs
# n=10; for i in `seq 1 $n`; do echo Test $i of $n; rtcwake -s10 -mmem;
date; echo Test $i done; done
5. Use 'Ctrl-a' then 'x' to exit QEMU console.
> ...
Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland
