diff options
| author | Dexuan Cui <decui@microsoft.com> | 2020-12-22 07:55:41 +0100 |
|---|---|---|
| committer | Wei Liu <wei.liu@kernel.org> | 2021-01-05 18:52:04 +0100 |
| commit | dfe94d4086e40e92b1926bddcefa629b791e9b28 (patch) | |
| tree | fb6fe7ef7968b71ca528444f532ecb757a358432 /drivers/hv | |
| parent | Linux 5.11-rc2 (diff) | |
| download | linux-dfe94d4086e40e92b1926bddcefa629b791e9b28.tar.xz linux-dfe94d4086e40e92b1926bddcefa629b791e9b28.zip | |
x86/hyperv: Fix kexec panic/hang issues
Currently the kexec kernel can panic or hang due to 2 causes:
1) hv_cpu_die() is not called upon kexec, so the hypervisor corrupts the
old VP Assist Pages when the kexec kernel runs. The same issue is fixed
for hibernation in commit 421f090c819d ("x86/hyperv: Suspend/resume the
VP assist page for hibernation"). Now fix it for kexec.
2) hyperv_cleanup() is called too early. In the kexec path, the other CPUs
are stopped in hv_machine_shutdown() -> native_machine_shutdown(), so
between hv_kexec_handler() and native_machine_shutdown(), the other CPUs
can still try to access the hypercall page and cause panic. The workaround
"hv_hypercall_pg = NULL;" in hyperv_cleanup() is unreliabe. Move
hyperv_cleanup() to a better place.
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20201222065541.24312-1-decui@microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Diffstat (limited to 'drivers/hv')
| -rw-r--r-- | drivers/hv/vmbus_drv.c | 2 |
1 files changed, 0 insertions, 2 deletions
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index 502f8cd95f6d..d491fdcee61f 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -2550,7 +2550,6 @@ static void hv_kexec_handler(void) /* Make sure conn_state is set as hv_synic_cleanup checks for it */ mb(); cpuhp_remove_state(hyperv_cpuhp_online); - hyperv_cleanup(); }; static void hv_crash_handler(struct pt_regs *regs) @@ -2566,7 +2565,6 @@ static void hv_crash_handler(struct pt_regs *regs) cpu = smp_processor_id(); hv_stimer_cleanup(cpu); hv_synic_disable_regs(cpu); - hyperv_cleanup(); }; static int hv_synic_suspend(void) |