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Diffstat (limited to 'gitlab/issues/target_missing/host_missing/accel_TCG/2634.toml')
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1 files changed, 0 insertions, 185 deletions
diff --git a/gitlab/issues/target_missing/host_missing/accel_TCG/2634.toml b/gitlab/issues/target_missing/host_missing/accel_TCG/2634.toml deleted file mode 100644 index 5899bd8d2..000000000 --- a/gitlab/issues/target_missing/host_missing/accel_TCG/2634.toml +++ /dev/null @@ -1,185 +0,0 @@ -id = 2634 -title = "Replay/record does not work with `rrsnapshot`/`loadvm`" -state = "opened" -created_at = "2024-10-21T13:18:30.992Z" -closed_at = "n/a" -labels = ["accel: TCG", "icount"] -url = "https://gitlab.com/qemu-project/qemu/-/issues/2634" -host-os = "Ubuntu 20.04.6 LTS" -host-arch = "x86_64" -qemu-version = "9.1.0" -guest-os = "alpine-standard-3.20.3-x86_64.iso" -guest-arch = "x86_64" -description = """Qemu's record/replay feature does not properly work when using snapshots (like rrsnapshot). - -Record/replay without snapshotting works just fine, but when using `rrsnapshot=...` the replay is stuck at boot. `loadvm` monitor command also gets qemu stuck. - -Record command: - -``` -$ qemu-system-x86_64 \\ - -cpu SandyBridge -smp 1 \\ - -serial stdio -display none \\ - -m 4096 \\ - -drive file=./empty.qcow2,id=rr \\ - -kernel ./boot/vmlinuz-lts \\ - -initrd ./boot/initramfs-lts . - -monitor telnet::12345,server,nowait \\ - -append "console=ttyS0 root=/dev/ram0 alpine_dev=cdrom:iso9660 modules=loop,squashfs,sd-mod,usb-storage quiet" \\ - -icount shift=auto,rrfile=rr,rr=record,rrsnapshot=init -``` - -Broken replay command, which gets qemu stuck: - -``` -$ qemu-system-x86_64 \\ - -cpu SandyBridge -smp 1 \\ - -serial stdio -display none \\ - -m 4096 \\ - -drive file=./empty.qcow2,id=rr \\ - -kernel ./boot/vmlinuz-lts \\ - -initrd ./boot/initramfs-lts . - -monitor telnet::12345,server,nowait \\ - -append "console=ttyS0 root=/dev/ram0 alpine_dev=cdrom:iso9660 modules=loop,squashfs,sd-mod,usb-storage quiet" \\ - -icount shift=auto,rrfile=rr,rr=replay,rrsnapshot=init - -qemu-system-x86_64: warning: TCG doesn't support requested feature: CPUID.01H:ECX.tsc-deadline [bit 24] -``` - -Record/replay without `rrsnapshot`/`loadvm`/etc works as expected.""" -reproduce = """To reproduce i've used alpine linux kernel as the guest: - -``` -wget https://dl-cdn.alpinelinux.org/alpine/v3.20/releases/x86_64/alpine-standard-3.20.3-x86_64.iso -7z x alpine-standard-3.20.3-x86_64.iso -``` - -Prerequisites - an empty qcow2 file for snapshots: - -``` -qemu-img create -f qcow2 empty.qcow2 1G -``` - -Running an alpine linux kernel with `rr=record` - works just fine, kernel boots, accepts input. - -``` -$ qemu-system-x86_64 \\ - -cpu SandyBridge -smp 1 \\ - -serial stdio -display none \\ - -m 4096 \\ - -drive file=./empty.qcow2,id=rr \\ - -kernel ./boot/vmlinuz-lts \\ - -initrd ./boot/initramfs-lts . - -monitor telnet::12345,server,nowait \\ - -append "console=ttyS0 root=/dev/ram0 alpine_dev=cdrom:iso9660 modules=loop,squashfs,sd-mod,usb-storage quiet" \\ - -icount shift=auto,rrfile=rr,rr=record,rrsnapshot=init - -qemu-system-x86_64: warning: TCG doesn't support requested feature: CPUID.01H:ECX.tsc-deadline [bit 24] -mount: mounting /dev/ram0 on /sysroot failed: Invalid argument -Mounting root failed. -initramfs emergency recovery shell launched. Type 'exit' to continue boot -sh: can't access tty; job control turned off -~ # ls -alh -total 32K -drwx------ 18 root root 0 Oct 21 13:02 . -drwx------ 18 root root 0 Oct 21 13:02 .. --rw------- 1 root root 8 Oct 21 13:02 .ash_history -drwxr-xr-x 2 root root 0 Jun 18 12:44 .modloop -drwxr-xr-x 2 root root 0 Oct 21 13:02 bin -drwxr-xr-x 9 root root 2.5K Oct 21 13:02 dev -drwxr-xr-x 4 root root 0 Oct 21 13:02 etc --rwxr-xr-x 1 root root 25.9K Jun 18 12:44 init -drwxr-xr-x 5 root root 0 Jun 18 12:44 lib -drwxr-xr-x 5 root root 0 Jun 18 12:44 media -drwxr-xr-x 2 root root 0 Jun 18 12:44 newroot -dr-xr-xr-x 114 root root 0 Oct 21 13:02 proc -drwx------ 2 root root 0 Sep 4 12:53 root -drwxr-xr-x 3 root root 0 Oct 21 13:02 run -drwxr-xr-x 2 root root 0 Oct 21 13:02 sbin -dr-xr-xr-x 13 root root 0 Oct 21 13:02 sys -drwxr-xr-x 2 root root 0 Oct 21 13:02 sysroot -drwxr-xr-x 2 root root 0 Oct 21 13:02 tmp -drwxr-xr-x 5 root root 0 Oct 21 13:02 usr -drwxr-xr-x 3 root root 0 Jun 18 12:44 var -~ # echo "AAAAAAAA?" -AAAAAAAA? -~ # -``` - -`rr`-file is produced, which can be used for replaying **without** `rrsnapshot`-option: - -``` -$ qemu-system-x86_64 \\ - -cpu SandyBridge -smp 1 \\ - -serial stdio -display none \\ - -m 4096 \\ - -drive file=./empty.qcow2,id=rr \\ - -kernel ./boot/vmlinuz-lts \\ - -initrd ./boot/initramfs-lts . - -monitor telnet::12345,server,nowait \\ - -append "console=ttyS0 root=/dev/ram0 alpine_dev=cdrom:iso9660 modules=loop,squashfs,sd-mod,usb-storage quiet" \\ - -icount shift=auto,rrfile=rr,rr=replay - -qemu-system-x86_64: warning: TCG doesn't support requested feature: CPUID.01H:ECX.tsc-deadline [bit 24] -mount: mounting /dev/ram0 on /sysroot failed: Invalid argument -Mounting root failed. -initramfs emergency recovery shell launched. Type 'exit' to continue boot -sh: can't access tty; job control turned off -~ # ls -alh -total 32K -drwx------ 18 root root 0 Oct 21 13:02 . -drwx------ 18 root root 0 Oct 21 13:02 .. --rw------- 1 root root 8 Oct 21 13:02 .ash_history -drwxr-xr-x 2 root root 0 Jun 18 12:44 .modloop -drwxr-xr-x 2 root root 0 Oct 21 13:02 bin -drwxr-xr-x 9 root root 2.5K Oct 21 13:02 dev -drwxr-xr-x 4 root root 0 Oct 21 13:02 etc --rwxr-xr-x 1 root root 25.9K Jun 18 12:44 init -drwxr-xr-x 5 root root 0 Jun 18 12:44 lib -drwxr-xr-x 5 root root 0 Jun 18 12:44 media -drwxr-xr-x 2 root root 0 Jun 18 12:44 newroot -dr-xr-xr-x 114 root root 0 Oct 21 13:02 proc -drwx------ 2 root root 0 Sep 4 12:53 root -drwxr-xr-x 3 root root 0 Oct 21 13:02 run -drwxr-xr-x 2 root root 0 Oct 21 13:02 sbin -dr-xr-xr-x 13 root root 0 Oct 21 13:02 sys -drwxr-xr-x 2 root root 0 Oct 21 13:02 sysroot -drwxr-xr-x 2 root root 0 Oct 21 13:02 tmp -drwxr-xr-x 5 root root 0 Oct 21 13:02 usr -drwxr-xr-x 3 root root 0 Jun 18 12:44 var -~ # echo "AAAAAAAA?" -AAAAAAAA? -~ # -``` - -As you can see, replaying emulation session works as expected. How ever, if I add the `rrsnapshot`-option, it gets stuck: - -``` -$ qemu-system-x86_64 \\ - -cpu SandyBridge -smp 1 \\ - -serial stdio -display none \\ - -m 4096 \\ - -drive file=./empty.qcow2,id=rr \\ - -kernel ./boot/vmlinuz-lts \\ - -initrd ./boot/initramfs-lts . - -monitor telnet::12345,server,nowait \\ - -append "console=ttyS0 root=/dev/ram0 alpine_dev=cdrom:iso9660 modules=loop,squashfs,sd-mod,usb-storage quiet" \\ - -icount shift=auto,rrfile=rr,rr=replay,rrsnapshot=init - -qemu-system-x86_64: warning: TCG doesn't support requested feature: CPUID.01H:ECX.tsc-deadline [bit 24] -``` - -This also can be reproduced without `rrsnapshot` option, by issuing `loadvm init` from qemu monitor: - -``` -$ telnet localhost 12345 -qemu> loadvm init -... -``` - -Or, by using `gdb` and issuing reverse-commands that require `loadvm` to load previous state, like `reverse-stepi` or `reverse-continue`. - -Attaching a debugger & using debug-prints shows some thread being stuck in the [`rcu.c`](https://gitlab.com/qemu-project/qemu/-/blob/master/util/rcu.c), near the `qemu_event_wait(&rcu_call_ready_event);`. I've tried to wait for quite some time (about an hour) and there was no result.""" -additional = """**Qemu build.** Qemu binary built from sources of 9.1.0 with `--target-list=x86_64-softmmu`. - -**Host machine.** An almost clean Ubuntu 20.04 with necessary packages for building qemu from the latest release sources.""" |