diff options
| author | Stephen Brennan | 2022-02-14 17:37:35 -0800 |
|---|---|---|
| committer | Wei Liu | 2022-02-18 13:09:38 +0000 |
| commit | d57d6fe5bf3463aad1332ecfc7555a6888b04fd9 (patch) | |
| tree | e7fe0e7acafcf85291cff7dfd4355ee6984cb296 /drivers/hv | |
| parent | 6de74d1069b821e96460d0fc2edfc35785db04fb (diff) | |
drivers: hv: log when enabling crash_kexec_post_notifiers
Recently I went down a rabbit hole looking at a race condition in
panic() on a Hyper-V guest. I assumed, since it was missing from the
command line, that crash_kexec_post_notifiers was disabled. Only after
a rather long reproduction and analysis process did I learn that Hyper-V
actually enables this setting unconditionally.
Users and debuggers alike would like to know when these things happen. I
think it would be good to print a message to the kernel log when this
happens, so that a grep for "crash_kexec_post_notifiers" shows relevant
results.
Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20220215013735.358327-1-stephen.s.brennan@oracle.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Diffstat (limited to 'drivers/hv')
| -rw-r--r-- | drivers/hv/hv_common.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c index 181d16bbf49d..c1dd21d0d7ef 100644 --- a/drivers/hv/hv_common.c +++ b/drivers/hv/hv_common.c @@ -79,8 +79,10 @@ int __init hv_common_init(void) * calling crash enlightment interface before running kdump * kernel. */ - if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) + if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) { crash_kexec_post_notifiers = true; + pr_info("Hyper-V: enabling crash_kexec_post_notifiers\n"); + } /* * Allocate the per-CPU state for the hypercall input arg. |