Am Wed, May 21, 2025 at 11:24:52PM +0200 schrieb Alexandre Chartre:
On Linux 6.1.135 every works fine with both the 20250211 and 20250512 microcode releases (kern.log is attached as 6.1.135-feb-microcode.log and 6.1.135-may-microcode.log)
With 6.1.139 and the February microcode, oopses appear related to clear_bhb_loop() (which may be related to "x86/its: Align RETs in BHB clear sequence to avoid thunking"?). This is captured in 6.1.139-feb-microcode.log.
With 6.1.139 and the May microcode, the system mostly crashes on bootup (in my tests it crashed in three out of four attempts). I've captured both the crash (6.1.139-may-microcode-crash.log) and a working boot (6.1.139-may-microcode-noncrash.log).
If you need any additional information, please let me know!
After looking at your crash logs in more detail, I suspect that your issue is the same root cause as spotted as well for the 5.15 series in https://lore.kernel.org/all/81cd1d38-8856-4b27-921d-839d9e385942@oracle.com/
I assume you can confirm as well that disabling the ITS mitigation with indirect_target_selection=off makes the system boot?
Regards, Salvatore
And this should be fixed by this patch:
x86/modules: Set VM_FLUSH_RESET_PERMS in module_alloc()
Confirmed: Running 6.1.139 plus "x86/modules: Set VM_FLUSH_RESET_PERMS in module_alloc()" resolves the issue: I've rebooted the affected server four times with a custom build and the oopses are gone and it reboots reliably.
Cheers, Moritz