Hi, Thorsten here, the Linux kernel's regression tracker. I noticed a report about a regression in bugzilla.kernel.org that appears to be related to the simpledrm driver. As many (most?) kernel developers don't keep an eye on the bug tracker, I decided to write this mail. To quote from https://bugzilla.kernel.org/show_bug.cgi?id=219007 : > Colin Ian King 2024-07-05 16:05:27 UTC > > The following code when run as root on a Debian sid amd64 server > running in virt-manager (KVM QEMU) will shut the system down with > 6.10.0-rc6. The fork() is required to cause racing on the open/close on > /dev/dri/card0 > > #include <fcntl.h> > #include <unistd.h> > > int main(void) > { > pid_t pid = fork(); > > while (1) { > int fd; > > fd = openat(AT_FDCWD, "/dev/dri/card0", O_WRONLY|O_NONBLOCK|O_SYNC); > close(fd); > } > } > > This was originally found using: while true; do sudo ./stress-ng > --dev 4 --dev-file /dev/dri/card0 -t 5; done and narrowed down to the > above reproducer. (cf: > https://github.com/ColinIanKing/stress-ng/issues/407 ) > > This does not occur on pre 6.10 kernels, so it looks like a 6.10 regression. See the ticket for more details, which also contains a dmesg from a boot in the VM: https://bugzilla.kernel.org/attachment.cgi?id=306610 Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat) -- Everything you wanna know about Linux kernel regression tracking: https://linux-regtracking.leemhuis.info/about/#tldr If I did something stupid, please tell me, as explained on that page. P.S.: let me use this mail to also add the report to the list of tracked regressions to ensure it's doesn't fall through the cracks: #regzbot introduced: v6.9..v6.10 #regzbot title: drm: opening and closing /dev/dri/card0 in a QEMU KVM instance will shutdown system #regzbot from: Colin Ian King <colin.i.king@xxxxxxxxx> #regzbot duplicate: https://bugzilla.kernel.org/show_bug.cgi?id=219007 #regzbot ignore-activity
