diff options
| author | Vitaly Kuznetsov <vkuznets@redhat.com> | 2015-08-02 01:08:09 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-08-05 07:28:38 +0200 |
| commit | b4370df2b1f5158de028e167974263c5757b34a6 (patch) | |
| tree | 4a8733a8b1ae446e1b1a3df70f7c180f8bc15ecf /arch/x86/kernel/cpu/mshyperv.c | |
| parent | Drivers: hv: don't do hypercalls when hypercall_page is NULL (diff) | |
| download | linux-b4370df2b1f5158de028e167974263c5757b34a6.tar.xz linux-b4370df2b1f5158de028e167974263c5757b34a6.zip | |
Drivers: hv: vmbus: add special crash handler
Full kernel hang is observed when kdump kernel starts after a crash. This
hang happens in vmbus_negotiate_version() function on
wait_for_completion() as Hyper-V host (Win2012R2 in my testing) never
responds to CHANNELMSG_INITIATE_CONTACT as it thinks the connection is
already established. We need to perform some mandatory minimalistic
cleanup before we start new kernel.
Reported-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86/kernel/cpu/mshyperv.c')
| -rw-r--r-- | arch/x86/kernel/cpu/mshyperv.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c index fa483ed4756e..5ea5bbcc85b3 100644 --- a/arch/x86/kernel/cpu/mshyperv.c +++ b/arch/x86/kernel/cpu/mshyperv.c @@ -35,6 +35,7 @@ struct ms_hyperv_info ms_hyperv; EXPORT_SYMBOL_GPL(ms_hyperv); static void (*hv_kexec_handler)(void); +static void (*hv_crash_handler)(struct pt_regs *regs); #if IS_ENABLED(CONFIG_HYPERV) static void (*vmbus_handler)(void); @@ -83,6 +84,18 @@ void hv_remove_kexec_handler(void) hv_kexec_handler = NULL; } EXPORT_SYMBOL_GPL(hv_remove_kexec_handler); + +void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs)) +{ + hv_crash_handler = handler; +} +EXPORT_SYMBOL_GPL(hv_setup_crash_handler); + +void hv_remove_crash_handler(void) +{ + hv_crash_handler = NULL; +} +EXPORT_SYMBOL_GPL(hv_remove_crash_handler); #endif static void hv_machine_shutdown(void) @@ -92,6 +105,14 @@ static void hv_machine_shutdown(void) native_machine_shutdown(); } +static void hv_machine_crash_shutdown(struct pt_regs *regs) +{ + if (hv_crash_handler) + hv_crash_handler(regs); + native_machine_crash_shutdown(regs); +} + + static uint32_t __init ms_hyperv_platform(void) { u32 eax; @@ -165,6 +186,7 @@ static void __init ms_hyperv_init_platform(void) #endif machine_ops.shutdown = hv_machine_shutdown; + machine_ops.crash_shutdown = hv_machine_crash_shutdown; } const __refconst struct hypervisor_x86 x86_hyper_ms_hyperv = { |