Re: [RFC PATCH] x86, hyperv: fix kernel panic when kexec on HyperV VM

2019-03-05 Thread Kairui Song
On Tue, Mar 5, 2019 at 8:28 PM Peter Zijlstra wrote: > > On Wed, Feb 27, 2019 at 10:55:46PM +0800, Kairui Song wrote: > > On Wed, Feb 27, 2019 at 8:02 PM Peter Zijlstra wrote: > > > > > > On Tue, Feb 26, 2019 at 11:56:15PM +0800, Kairui Song wrote: > > > > arch/x86/hyperv/hv_init.c | 4 > >

Re: [RFC PATCH] x86, hyperv: fix kernel panic when kexec on HyperV VM

2019-03-05 Thread Peter Zijlstra
On Wed, Feb 27, 2019 at 10:55:46PM +0800, Kairui Song wrote: > On Wed, Feb 27, 2019 at 8:02 PM Peter Zijlstra wrote: > > > > On Tue, Feb 26, 2019 at 11:56:15PM +0800, Kairui Song wrote: > > > arch/x86/hyperv/hv_init.c | 4 > > > 1 file changed, 4 insertions(+) > > > > > > diff --git

Re: [RFC PATCH] x86, hyperv: fix kernel panic when kexec on HyperV VM

2019-02-27 Thread Kairui Song
On Wed, Feb 27, 2019 at 8:02 PM Peter Zijlstra wrote: > > On Tue, Feb 26, 2019 at 11:56:15PM +0800, Kairui Song wrote: > > arch/x86/hyperv/hv_init.c | 4 > > 1 file changed, 4 insertions(+) > > > > diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c > > index

Re: [RFC PATCH] x86, hyperv: fix kernel panic when kexec on HyperV VM

2019-02-27 Thread Peter Zijlstra
On Tue, Feb 26, 2019 at 11:56:15PM +0800, Kairui Song wrote: > arch/x86/hyperv/hv_init.c | 4 > 1 file changed, 4 insertions(+) > > diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c > index 7abb09e2eeb8..92291c18d716 100644 > --- a/arch/x86/hyperv/hv_init.c > +++

Re: [RFC PATCH] x86, hyperv: fix kernel panic when kexec on HyperV VM

2019-02-26 Thread Vitaly Kuznetsov
Kairui Song writes: > When hypercalls is used for sending IPIs, kexec will fail with a kernel > panic like this: > > kexec_core: Starting new kernel > BUG: unable to handle kernel NULL pointer dereference at > PGD 800057995067 P4D 800057995067 PUD 57990067 PMD 0 > Oops:

[RFC PATCH] x86, hyperv: fix kernel panic when kexec on HyperV VM

2019-02-26 Thread Kairui Song
When hypercalls is used for sending IPIs, kexec will fail with a kernel panic like this: kexec_core: Starting new kernel BUG: unable to handle kernel NULL pointer dereference at PGD 800057995067 P4D 800057995067 PUD 57990067 PMD 0 Oops: 0002 [#1] SMP PTI CPU: 0 PID: 1016