diff options
author | Vitaly Kuznetsov <vkuznets@redhat.com> | 2017-01-28 12:37:14 -0700 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-01-31 11:05:58 +0100 |
commit | d6f3609d2b4c6d0eec01f398cb685e50da3e6013 (patch) | |
tree | e4810aaa4fee18f5876d13c6a0376ed72685fc6d /arch/x86/hyperv | |
parent | 17244623a4c0f68d3f02c9c74d9b6ae259425826 (diff) | |
download | linux-d6f3609d2b4c6d0eec01f398cb685e50da3e6013.tar.bz2 |
Drivers: hv: restore hypervcall page cleanup before kexec
We need to cleanup the hypercall page before doing kexec/kdump or the new
kernel may crash if it tries to use it. Reuse the now-empty hv_cleanup
function renaming it to hyperv_cleanup and moving to the arch specific
code.
Fixes: 8730046c1498 ("Drivers: hv vmbus: Move Hypercall page setup out of common code")
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/hyperv')
-rw-r--r-- | arch/x86/hyperv/hv_init.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c index d289bc29d282..d6b018b86c42 100644 --- a/arch/x86/hyperv/hv_init.c +++ b/arch/x86/hyperv/hv_init.c @@ -166,6 +166,22 @@ void hyperv_init(void) } /* + * This routine is called before kexec/kdump, it does the required cleanup. + */ +void hyperv_cleanup(void) +{ + union hv_x64_msr_hypercall_contents hypercall_msr; + + /* Reset our OS id */ + wrmsrl(HV_X64_MSR_GUEST_OS_ID, 0); + + /* Reset the hypercall page */ + hypercall_msr.as_uint64 = 0; + wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64); +} +EXPORT_SYMBOL_GPL(hyperv_cleanup); + +/* * hv_do_hypercall- Invoke the specified hypercall */ u64 hv_do_hypercall(u64 control, void *input, void *output) |