Am 03.03.2023 um 23:51 hat Maciej S. Szmigiero geschrieben: > On 8.02.2023 12:19, Cédric Le Goater wrote: > > On 2/7/23 13:48, Kevin Wolf wrote: > > > Am 07.02.2023 um 10:19 hat Cédric Le Goater geschrieben: > > > > On 2/7/23 09:38, Kevin Wolf wrote: > > > > > Am 06.02.2023 um 16:54 hat Cédric Le Goater geschrieben: > > > > > > On 1/20/23 13:25, Kevin Wolf wrote: > > > > > > > From: Xiang Zheng <zhengxia...@huawei.com> > > > > > > > > > > > > > > Currently we fill the VIRT_FLASH memory space with two 64MB NOR > > > > > > > images > > > > > > > when using persistent UEFI variables on virt board. Actually we > > > > > > > only use > > > > > > > a very small(non-zero) part of the memory while the rest > > > > > > > significant > > > > > > > large(zero) part of memory is wasted. > > > > > > > > > > > > > > So this patch checks the block status and only writes the > > > > > > > non-zero part > > > > > > > into memory. This requires pflash devices to use sparse files for > > > > > > > backends. > > > > > > > > > > > > > > Signed-off-by: Xiang Zheng <zhengxia...@huawei.com> > > > > > > > > > > > > > > [ kraxel: rebased to latest master ] > > > > > > > > > > > > > > Signed-off-by: Gerd Hoffmann <kra...@redhat.com> > > > > > > > Message-Id: <20221220084246.1984871-1-kra...@redhat.com> > > > > > > > Reviewed-by: Daniel P. Berrangé <berra...@redhat.com> > > > > > > > Reviewed-by: Kevin Wolf <kw...@redhat.com> > > > > > > > Signed-off-by: Kevin Wolf <kw...@redhat.com> > > > > > > > > > > > > This newly merged patch introduces a "regression" when booting an > > > > > > Aspeed > > > > > > machine. The following extra m25p80 patch (not yet merged) is > > > > > > required > > > > > > for the issue to show: > > > > > > > > > > > > > > > > > > https://lore.kernel.org/qemu-devel/20221115151000.2080833-1-...@kaod.org/ > > > > > > > > > > > > U-Boot fails to find the filesystem in that case. > > > > > > > > > > > > It can be easily reproduced with the witherspoon-bmc machine and > > > > > > seems > > > > > > to be related to the use of a UBI filesystem. Other Aspeed machines > > > > > > not > > > > > > using UBI are not impacted. > > > > > > > > > > > > Here is a tentative fix. I don't know enough the block layer to > > > > > > explain > > > > > > what is happening :/ > > > > > > > > > > I was puzzled for a moment, but... > > > > > > > > > > > @@ -39,7 +39,7 @@ static int blk_pread_nonzeroes(BlockBack > > > > > > return ret; > > > > > > } > > > > > > if (!(ret & BDRV_BLOCK_ZERO)) { > > > > > > - ret = bdrv_pread(bs->file, offset, bytes, > > > > > > > > > > 'bs->file' rather than 'bs' really looks wrong. I think replacing that > > > > > would already fix the bug you're seeing. > > > > > > > > > > Just to be sure, how did you configure the block backend? bs->file > > > > > would > > > > > happen to work more or less with raw over file-posix (which is > > > > > probably > > > > > what Gerd tested), but I think it breaks with anything else. > > > > > > > > The command is : > > > > > > > > $ qemu-system-arm -M witherspoon-bmc -net user \ > > > > -drive file=/path/to/file.mtd,format=raw,if=mtd \ > > > > -nographic -serial mon:stdio -snapshot > > > > > > > > If I remove '-snapshot', all works fine. > > > > > > Ok, that makes sense then. -snapshot creates a temporary qcow2 overlay, > > > and then what your guest sees with bs->file is not the virtual disk > > > content of the qcow2 image, but the qcow2 file itself. > > > > yes. Same symptom with pflash devices, TCG and KVM. The guest hangs with > > -snapshot. > > > > C. > > > > qemu-system-aarch64 -M virt -smp 2 -cpu max -accel tcg,thread=multi > > -nographic -m 2G -drive > > if=pflash,format=raw,file=/usr/share/edk2/aarch64/QEMU_EFI-silent-pflash.raw,readonly=on > > -drive if=pflash,format=raw,file=rhel9-varstore.img -device > > virtio-net,netdev=net0,bus=pcie.0,addr=0x3 -netdev user,id=net0 -drive > > file=rhel9-arm64.qcow2,if=none,id=disk,format=qcow2,cache=none -device > > virtio-blk-device,drive=disk -serial mon:stdio -snapshot > > > > > > > > +1 here for QEMU + KVM/x86: OVMF CODE file fails to load (is all zeroes) > with either "-snapshot" QEMU command line option or even with just > "snapshot=on" > setting enabled on pflash0. > > Reverting this patch seems to fix the issue.
Hm, so we know the fix, but nobody has submitted it as an actual patch? I'll send one... Kevin
