Messages in this thread | ![/](/images/icornerl.gif) | | Date | Mon, 16 Jan 2023 07:45:26 +0100 | Subject | Re: [PATCH] x86/acpi: fix suspend with Xen | From | Juergen Gross <> |
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On 13.01.23 20:40, Rafael J. Wysocki wrote: > On Fri, Jan 13, 2023 at 3:06 PM Juergen Gross <jgross@suse.com> wrote: >> >> Commit f1e525009493 ("x86/boot: Skip realmode init code when running as >> Xen PV guest") missed one code path accessing real_mode_header, leading >> to dereferencing NULL when suspending the system under Xen: >> >> [ 348.284004] PM: suspend entry (deep) >> [ 348.289532] Filesystems sync: 0.005 seconds >> [ 348.291545] Freezing user space processes ... (elapsed 0.000 seconds) done. >> [ 348.292457] OOM killer disabled. >> [ 348.292462] Freezing remaining freezable tasks ... (elapsed 0.104 seconds) done. >> [ 348.396612] printk: Suspending console(s) (use no_console_suspend to debug) >> [ 348.749228] PM: suspend devices took 0.352 seconds >> [ 348.769713] ACPI: EC: interrupt blocked >> [ 348.816077] BUG: kernel NULL pointer dereference, address: 000000000000001c >> [ 348.816080] #PF: supervisor read access in kernel mode >> [ 348.816081] #PF: error_code(0x0000) - not-present page >> [ 348.816083] PGD 0 P4D 0 >> [ 348.816086] Oops: 0000 [#1] PREEMPT SMP NOPTI >> [ 348.816089] CPU: 0 PID: 6764 Comm: systemd-sleep Not tainted 6.1.3-1.fc32.qubes.x86_64 #1 >> [ 348.816092] Hardware name: Star Labs StarBook/StarBook, BIOS 8.01 07/03/2022 >> [ 348.816093] RIP: e030:acpi_get_wakeup_address+0xc/0x20 >> >> Fix that by adding an indirection for acpi_get_wakeup_address() which >> Xen PV dom0 can use to return a dummy non-zero wakeup address (this >> address won't ever be used, as the real suspend handling is done by the >> hypervisor). > > How exactly does this help?
I believed the first sentence of the commit message would make this clear enough.
I can expand the commit message to go more into detail if you think this is really needed.
Juergen [unhandled content-type:application/pgp-keys][unhandled content-type:application/pgp-signature] | ![\](/images/icornerr.gif) |