diff options
author | Vitaly Kuznetsov <vkuznets@redhat.com> | 2016-06-04 03:09:22 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-08-31 14:05:40 +0300 |
commit | a9f61ca793becabdefab03b77568d6c6f8c1bc79 (patch) | |
tree | 422f0e2eb47880341e6ebe69a1afa918458c4dd4 /drivers/hv/vmbus_drv.c | |
parent | 069b188f43d9a44422eb35a8f95533d2c44ad315 (diff) |
Drivers: hv: avoid vfree() on crash
When we crash from NMI context (e.g. after NMI injection from host when
'sysctl -w kernel.unknown_nmi_panic=1' is set) we hit
kernel BUG at mm/vmalloc.c:1530!
as vfree() is denied. While the issue could be solved with in_nmi() check
instead I opted for skipping vfree on all sorts of crashes to reduce the
amount of work which can cause consequent crashes. We don't really need to
free anything on crash.
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 'drivers/hv/vmbus_drv.c')
-rw-r--r-- | drivers/hv/vmbus_drv.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index e82f7e1c217c..fedf6298ec0b 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -874,7 +874,7 @@ err_alloc: bus_unregister(&hv_bus); err_cleanup: - hv_cleanup(); + hv_cleanup(false); return ret; } @@ -1326,7 +1326,7 @@ static void hv_kexec_handler(void) vmbus_initiate_unload(false); for_each_online_cpu(cpu) smp_call_function_single(cpu, hv_synic_cleanup, NULL, 1); - hv_cleanup(); + hv_cleanup(false); }; static void hv_crash_handler(struct pt_regs *regs) @@ -1338,7 +1338,7 @@ static void hv_crash_handler(struct pt_regs *regs) * for kdump. */ hv_synic_cleanup(NULL); - hv_cleanup(); + hv_cleanup(true); }; static int __init hv_acpi_init(void) @@ -1398,7 +1398,7 @@ static void __exit vmbus_exit(void) &hyperv_panic_block); } bus_unregister(&hv_bus); - hv_cleanup(); + hv_cleanup(false); for_each_online_cpu(cpu) { tasklet_kill(hv_context.event_dpc[cpu]); smp_call_function_single(cpu, hv_synic_cleanup, NULL, 1); |