| Message ID | 20240108160900.104835-1-kraxel@redhat.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | hw/pflash: implement update buffer for block writes | expand |
On 8/1/24 17:08, Gerd Hoffmann wrote: > Gerd Hoffmann (3): > hw/pflash: refactor pflash_data_write() > hw/pflash: use ldn_{be,le}_p and stn_{be,le}_p > hw/pflash: implement update buffer for block writes Series: Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org> and queued, thanks!
08.01.2024 19:08, Gerd Hoffmann: > When running qemu with edk2 efi firmware on aarch64 the efi > variable store in pflash can get corrupted. qemu not doing > proper block writes -- flush all or nothing to storage -- is > a hot candidate for being the root cause. > > This little series tries to fix that with an update buffer > where block writes are staged, so we can commit or discard > the changes when the block write is completed or canceled. It looks like we can pick this up for stable too. It's not usual to pick up new features for stable, but this one fixes actual bug and if not applied, can easily lead to data corruption. I'd pick it up for 8.2.x and 8.1.x at least. Thoughts? Thanks, /mjt
On Sat, Jan 20, 2024 at 01:18:14PM +0300, Michael Tokarev wrote: > 08.01.2024 19:08, Gerd Hoffmann: > > When running qemu with edk2 efi firmware on aarch64 the efi > > variable store in pflash can get corrupted. qemu not doing > > proper block writes -- flush all or nothing to storage -- is > > a hot candidate for being the root cause. > > > > This little series tries to fix that with an update buffer > > where block writes are staged, so we can commit or discard > > the changes when the block write is completed or canceled. > > It looks like we can pick this up for stable too. It's not > usual to pick up new features for stable, but this one fixes > actual bug and if not applied, can easily lead to data corruption. > > I'd pick it up for 8.2.x and 8.1.x at least. Well, it turned out there was a edk2 bug causing flash corruption. While debugging edk2 I was using a qemu build with fixed pflash. So on one hand I don't know for sure whenever the incorrect block flash emulation /alone/ can cause pflash corruption too. On the other hand the edk2 debugging session also was a stress test for the pflash fix, so I'm pretty confident it works correctly. I think it makes sense to include it. take care, Gerd
When running qemu with edk2 efi firmware on aarch64 the efi variable store in pflash can get corrupted. qemu not doing proper block writes -- flush all or nothing to storage -- is a hot candidate for being the root cause. This little series tries to fix that with an update buffer where block writes are staged, so we can commit or discard the changes when the block write is completed or canceled. v2: - add patch to use ldn_{be,le}_p and stn_{be,le}_p - add/update tracing Gerd Hoffmann (3): hw/pflash: refactor pflash_data_write() hw/pflash: use ldn_{be,le}_p and stn_{be,le}_p hw/pflash: implement update buffer for block writes hw/block/pflash_cfi01.c | 171 +++++++++++++++++++++------------------- hw/block/pflash_cfi02.c | 2 +- hw/block/trace-events | 7 +- 3 files changed, 97 insertions(+), 83 deletions(-)