Re: [PATCH] x86/cpu: Reinitialize IA32_FEAT_CTL MSR on BSP during wakeup
On Mon, Jun 08, 2020 at 10:29:21AM -0700, Sean Christopherson wrote: > On Mon, Jun 08, 2020 at 11:12:35AM +0100, Liam Merwick wrote: > > On 05/06/2020 21:07, Sean Christopherson wrote: > > >Reinitialize IA32_FEAT_CTL on the BSP during wakeup to handle the case > > >where firmware doesn't initialize or save/restore across S3. This fixes > > >a bug where IA32_FEAT_CTL is left uninitialized and results in VMXON > > >taking a #GP due to VMX not being fully enabled, i.e. breaks KVM. > > > > > >Use init_ia32_feat_ctl() to "restore" IA32_FEAT_CTL as it already deals > > >with the case where the MSR is locked, and because APs already redo > > >init_ia32_feat_ctl() during suspend by virtue of the SMP boot flow being > > >used to reinitialize APs upon wakeup. Do the call in the early wakeup > > >flow to avoid dependencies in the syscore_ops chain, e.g. simply adding > > >a resume hook is not guaranteed to work, as KVM does VMXON in its own > > >resume hook, kvm_resume(), when KVM has active guests. > > > > > >Reported-by: Brad Campbell > > >Cc: Maxim Levitsky > > >Cc: Paolo Bonzini > > >Cc: k...@vger.kernel.org > > > > Should it have the following tag since it fixes a commit introduced in 5.6? > > Cc: sta...@vger.kernel.org # v5.6 > > It definitely warrants a backport to v5.6. I didn't include a Cc to stable > because I swear I had seen an email fly by that stated an explicit Cc is > unnecessary/unwanted for tip-tree patches, but per a recent statement from > Boris it looks like I'm simply confused[*]. I'll add the Cc in v2. > > [*] https://lkml.kernel.org/r/20200417164752.gf7...@zn.tnic Yeah, I was simply parroting what Greg has told me. Maybe he should finally do that script. :-P Also, I believe Sasha's Skynet machine already does that... CCed both. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette
Re: [PATCH] x86/cpu: Reinitialize IA32_FEAT_CTL MSR on BSP during wakeup
On Mon, Jun 08, 2020 at 11:12:35AM +0100, Liam Merwick wrote:
> On 05/06/2020 21:07, Sean Christopherson wrote:
> >Reinitialize IA32_FEAT_CTL on the BSP during wakeup to handle the case
> >where firmware doesn't initialize or save/restore across S3. This fixes
> >a bug where IA32_FEAT_CTL is left uninitialized and results in VMXON
> >taking a #GP due to VMX not being fully enabled, i.e. breaks KVM.
> >
> >Use init_ia32_feat_ctl() to "restore" IA32_FEAT_CTL as it already deals
> >with the case where the MSR is locked, and because APs already redo
> >init_ia32_feat_ctl() during suspend by virtue of the SMP boot flow being
> >used to reinitialize APs upon wakeup. Do the call in the early wakeup
> >flow to avoid dependencies in the syscore_ops chain, e.g. simply adding
> >a resume hook is not guaranteed to work, as KVM does VMXON in its own
> >resume hook, kvm_resume(), when KVM has active guests.
> >
> >Reported-by: Brad Campbell
> >Cc: Maxim Levitsky
> >Cc: Paolo Bonzini
> >Cc: k...@vger.kernel.org
>
> Should it have the following tag since it fixes a commit introduced in 5.6?
> Cc: sta...@vger.kernel.org # v5.6
It definitely warrants a backport to v5.6. I didn't include a Cc to stable
because I swear I had seen an email fly by that stated an explicit Cc is
unnecessary/unwanted for tip-tree patches, but per a recent statement from
Boris it looks like I'm simply confused[*]. I'll add the Cc in v2.
[*] https://lkml.kernel.org/r/20200417164752.gf7...@zn.tnic
> >Fixes: 21bd3467a58e ("KVM: VMX: Drop initialization of IA32_FEAT_CTL MSR")
> >Signed-off-by: Sean Christopherson
>
> Reviewed-by: Liam Merwick
Re: [PATCH] x86/cpu: Reinitialize IA32_FEAT_CTL MSR on BSP during wakeup
On Fri, 2020-06-05 at 13:07 -0700, Sean Christopherson wrote:
> Reinitialize IA32_FEAT_CTL on the BSP during wakeup to handle the
> case
> where firmware doesn't initialize or save/restore across S3. This
> fixes
> a bug where IA32_FEAT_CTL is left uninitialized and results in VMXON
> taking a #GP due to VMX not being fully enabled, i.e. breaks KVM.
>
> Use init_ia32_feat_ctl() to "restore" IA32_FEAT_CTL as it already
> deals
> with the case where the MSR is locked, and because APs already redo
> init_ia32_feat_ctl() during suspend by virtue of the SMP boot flow
> being
> used to reinitialize APs upon wakeup. Do the call in the early
> wakeup
> flow to avoid dependencies in the syscore_ops chain, e.g. simply
> adding
> a resume hook is not guaranteed to work, as KVM does VMXON in its own
> resume hook, kvm_resume(), when KVM has active guests.
>
> Reported-by: Brad Campbell
> Cc: Maxim Levitsky
> Cc: Paolo Bonzini
> Cc: k...@vger.kernel.org
> Fixes: 21bd3467a58e ("KVM: VMX: Drop initialization of IA32_FEAT_CTL
> MSR")
> Signed-off-by: Sean Christopherson
> ---
> arch/x86/include/asm/cpu.h | 5 +
> arch/x86/kernel/cpu/cpu.h | 4
> arch/x86/power/cpu.c | 6 ++
> 3 files changed, 11 insertions(+), 4 deletions(-)
>
> diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h
> index dd17c2da1af5..da78ccbd493b 100644
> --- a/arch/x86/include/asm/cpu.h
> +++ b/arch/x86/include/asm/cpu.h
> @@ -58,4 +58,9 @@ static inline bool handle_guest_split_lock(unsigned
> long ip)
> return false;
> }
> #endif
> +#ifdef CONFIG_IA32_FEAT_CTL
> +void init_ia32_feat_ctl(struct cpuinfo_x86 *c);
> +#else
> +static inline void init_ia32_feat_ctl(struct cpuinfo_x86 *c) {}
> +#endif
> #endif /* _ASM_X86_CPU_H */
> diff --git a/arch/x86/kernel/cpu/cpu.h b/arch/x86/kernel/cpu/cpu.h
> index 37fdefd14f28..38ab6e115eac 100644
> --- a/arch/x86/kernel/cpu/cpu.h
> +++ b/arch/x86/kernel/cpu/cpu.h
> @@ -80,8 +80,4 @@ extern void x86_spec_ctrl_setup_ap(void);
>
> extern u64 x86_read_arch_cap_msr(void);
>
> -#ifdef CONFIG_IA32_FEAT_CTL
> -void init_ia32_feat_ctl(struct cpuinfo_x86 *c);
> -#endif
> -
> #endif /* ARCH_X86_CPU_H */
> diff --git a/arch/x86/power/cpu.c b/arch/x86/power/cpu.c
> index aaff9ed7ff45..b0d3c5ca6d80 100644
> --- a/arch/x86/power/cpu.c
> +++ b/arch/x86/power/cpu.c
> @@ -193,6 +193,8 @@ static void fix_processor_context(void)
> */
> static void notrace __restore_processor_state(struct saved_context
> *ctxt)
> {
> + struct cpuinfo_x86 *c;
> +
> if (ctxt->misc_enable_saved)
> wrmsrl(MSR_IA32_MISC_ENABLE, ctxt->misc_enable);
> /*
> @@ -263,6 +265,10 @@ static void notrace
> __restore_processor_state(struct saved_context *ctxt)
> mtrr_bp_restore();
> perf_restore_debug_store();
> msr_restore_context(ctxt);
> +
> + c = _data(smp_processor_id());
> + if (cpu_has(c, X86_FEATURE_MSR_IA32_FEAT_CTL))
> + init_ia32_feat_ctl(c);
> }
>
> /* Needed by apm.c */
I don't have currently an active VMX system to test this on,
but from the code and from my knowelege of this area this looks all
right.
Reviewed-by: Maxim Levitsky
Best regards,
Maxim Levitsky
Re: [PATCH] x86/cpu: Reinitialize IA32_FEAT_CTL MSR on BSP during wakeup
G'day Sean, With the addition of this patch on a vanilla v5.7 : Tested-by: Brad Campbell On 8/6/20 12:34 am, Sean Christopherson wrote: On Sat, Jun 06, 2020 at 05:08:38AM +0800, kernel test robot wrote: arch/x86/kernel/cpu/centaur.c: In function 'init_centaur': arch/x86/kernel/cpu/centaur.c:219:2: error: implicit declaration of function 'init_ia32_feat_ctl' [-Werror=implicit-function-declaration] 219 | init_ia32_feat_ctl(c); | ^~ cc1: some warnings being treated as errors -- arch/x86/kernel/cpu/zhaoxin.c: In function 'init_zhaoxin': arch/x86/kernel/cpu/zhaoxin.c:110:2: error: implicit declaration of function 'init_ia32_feat_ctl' [-Werror=implicit-function-declaration] 110 | init_ia32_feat_ctl(c); | ^~ cc1: some warnings being treated as errors Blech, zhaoxin.c an centaur.c don't include asm/cpu.h, and I (obviously) don't have them enabled in my configs. I'll wait a day or two more before sending v2. diff --git a/arch/x86/kernel/cpu/centaur.c b/arch/x86/kernel/cpu/centaur.c index 426792565d86..c5cf336e5077 100644 --- a/arch/x86/kernel/cpu/centaur.c +++ b/arch/x86/kernel/cpu/centaur.c @@ -3,6 +3,7 @@ #include #include +#include #include #include #include diff --git a/arch/x86/kernel/cpu/zhaoxin.c b/arch/x86/kernel/cpu/zhaoxin.c index df1358ba622b..05fa4ef63490 100644 --- a/arch/x86/kernel/cpu/zhaoxin.c +++ b/arch/x86/kernel/cpu/zhaoxin.c @@ -2,6 +2,7 @@ #include #include +#include #include #include "cpu.h"
Re: [PATCH] x86/cpu: Reinitialize IA32_FEAT_CTL MSR on BSP during wakeup
On 05/06/2020 21:07, Sean Christopherson wrote:
Reinitialize IA32_FEAT_CTL on the BSP during wakeup to handle the case
where firmware doesn't initialize or save/restore across S3. This fixes
a bug where IA32_FEAT_CTL is left uninitialized and results in VMXON
taking a #GP due to VMX not being fully enabled, i.e. breaks KVM.
Use init_ia32_feat_ctl() to "restore" IA32_FEAT_CTL as it already deals
with the case where the MSR is locked, and because APs already redo
init_ia32_feat_ctl() during suspend by virtue of the SMP boot flow being
used to reinitialize APs upon wakeup. Do the call in the early wakeup
flow to avoid dependencies in the syscore_ops chain, e.g. simply adding
a resume hook is not guaranteed to work, as KVM does VMXON in its own
resume hook, kvm_resume(), when KVM has active guests.
Reported-by: Brad Campbell
Cc: Maxim Levitsky
Cc: Paolo Bonzini
Cc: k...@vger.kernel.org
Should it have the following tag since it fixes a commit introduced in 5.6?
Cc: sta...@vger.kernel.org # v5.6
Fixes: 21bd3467a58e ("KVM: VMX: Drop initialization of IA32_FEAT_CTL MSR")
Signed-off-by: Sean Christopherson
Reviewed-by: Liam Merwick
---
arch/x86/include/asm/cpu.h | 5 +
arch/x86/kernel/cpu/cpu.h | 4
arch/x86/power/cpu.c | 6 ++
3 files changed, 11 insertions(+), 4 deletions(-)
diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h
index dd17c2da1af5..da78ccbd493b 100644
--- a/arch/x86/include/asm/cpu.h
+++ b/arch/x86/include/asm/cpu.h
@@ -58,4 +58,9 @@ static inline bool handle_guest_split_lock(unsigned long ip)
return false;
}
#endif
+#ifdef CONFIG_IA32_FEAT_CTL
+void init_ia32_feat_ctl(struct cpuinfo_x86 *c);
+#else
+static inline void init_ia32_feat_ctl(struct cpuinfo_x86 *c) {}
+#endif
#endif /* _ASM_X86_CPU_H */
diff --git a/arch/x86/kernel/cpu/cpu.h b/arch/x86/kernel/cpu/cpu.h
index 37fdefd14f28..38ab6e115eac 100644
--- a/arch/x86/kernel/cpu/cpu.h
+++ b/arch/x86/kernel/cpu/cpu.h
@@ -80,8 +80,4 @@ extern void x86_spec_ctrl_setup_ap(void);
extern u64 x86_read_arch_cap_msr(void);
-#ifdef CONFIG_IA32_FEAT_CTL
-void init_ia32_feat_ctl(struct cpuinfo_x86 *c);
-#endif
-
#endif /* ARCH_X86_CPU_H */
diff --git a/arch/x86/power/cpu.c b/arch/x86/power/cpu.c
index aaff9ed7ff45..b0d3c5ca6d80 100644
--- a/arch/x86/power/cpu.c
+++ b/arch/x86/power/cpu.c
@@ -193,6 +193,8 @@ static void fix_processor_context(void)
*/
static void notrace __restore_processor_state(struct saved_context *ctxt)
{
+ struct cpuinfo_x86 *c;
+
if (ctxt->misc_enable_saved)
wrmsrl(MSR_IA32_MISC_ENABLE, ctxt->misc_enable);
/*
@@ -263,6 +265,10 @@ static void notrace __restore_processor_state(struct
saved_context *ctxt)
mtrr_bp_restore();
perf_restore_debug_store();
msr_restore_context(ctxt);
+
+ c = _data(smp_processor_id());
+ if (cpu_has(c, X86_FEATURE_MSR_IA32_FEAT_CTL))
+ init_ia32_feat_ctl(c);
}
/* Needed by apm.c */
Re: [PATCH] x86/cpu: Reinitialize IA32_FEAT_CTL MSR on BSP during wakeup
On Sat, Jun 06, 2020 at 05:08:38AM +0800, kernel test robot wrote: arch/x86/kernel/cpu/centaur.c: In function 'init_centaur': > >> arch/x86/kernel/cpu/centaur.c:219:2: error: implicit declaration of > >> function 'init_ia32_feat_ctl' [-Werror=implicit-function-declaration] > 219 | init_ia32_feat_ctl(c); > | ^~ > cc1: some warnings being treated as errors > -- > arch/x86/kernel/cpu/zhaoxin.c: In function 'init_zhaoxin': > >> arch/x86/kernel/cpu/zhaoxin.c:110:2: error: implicit declaration of > >> function 'init_ia32_feat_ctl' [-Werror=implicit-function-declaration] > 110 | init_ia32_feat_ctl(c); > | ^~ > cc1: some warnings being treated as errors Blech, zhaoxin.c an centaur.c don't include asm/cpu.h, and I (obviously) don't have them enabled in my configs. I'll wait a day or two more before sending v2. diff --git a/arch/x86/kernel/cpu/centaur.c b/arch/x86/kernel/cpu/centaur.c index 426792565d86..c5cf336e5077 100644 --- a/arch/x86/kernel/cpu/centaur.c +++ b/arch/x86/kernel/cpu/centaur.c @@ -3,6 +3,7 @@ #include #include +#include #include #include #include diff --git a/arch/x86/kernel/cpu/zhaoxin.c b/arch/x86/kernel/cpu/zhaoxin.c index df1358ba622b..05fa4ef63490 100644 --- a/arch/x86/kernel/cpu/zhaoxin.c +++ b/arch/x86/kernel/cpu/zhaoxin.c @@ -2,6 +2,7 @@ #include #include +#include #include #include "cpu.h"
Re: [PATCH] x86/cpu: Reinitialize IA32_FEAT_CTL MSR on BSP during wakeup
Hi Sean, I love your patch! Yet something to improve: [auto build test ERROR on tip/x86/core] [also build test ERROR on tip/auto-latest v5.7 next-20200605] [cannot apply to bp/for-next] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system. BTW, we also suggest to use '--base' option to specify the base tree in git format-patch, please see https://stackoverflow.com/a/37406982] url: https://github.com/0day-ci/linux/commits/Sean-Christopherson/x86-cpu-Reinitialize-IA32_FEAT_CTL-MSR-on-BSP-during-wakeup/20200606-040921 base: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 9cb1fd0efd195590b828b9b865421ad345a4a145 config: x86_64-allyesconfig (attached as .config) compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 6dd738e2f0609f7d3313b574a1d471263d2d3ba1) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install x86_64 cross compiling tool for clang build # apt-get install binutils-x86-64-linux-gnu # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All errors (new ones prefixed by >>, old ones prefixed by <<): >> arch/x86/kernel/cpu/centaur.c:219:2: error: implicit declaration of function >> 'init_ia32_feat_ctl' [-Werror,-Wimplicit-function-declaration] init_ia32_feat_ctl(c); ^ 1 error generated. -- >> arch/x86/kernel/cpu/zhaoxin.c:110:2: error: implicit declaration of function >> 'init_ia32_feat_ctl' [-Werror,-Wimplicit-function-declaration] init_ia32_feat_ctl(c); ^ 1 error generated. vim +/init_ia32_feat_ctl +219 arch/x86/kernel/cpu/centaur.c 60882cc159e141 arch/x86/kernel/cpu/centaur.c David Wang 2018-04-20 218 501444905fcb41 arch/x86/kernel/cpu/centaur.c Sean Christopherson 2019-12-20 @219 init_ia32_feat_ctl(c); ^1da177e4c3f41 arch/i386/kernel/cpu/centaur.c Linus Torvalds 2005-04-16 220 } ^1da177e4c3f41 arch/i386/kernel/cpu/centaur.c Linus Torvalds 2005-04-16 221 :: The code at line 219 was first introduced by commit :: 501444905fcb4166589fda99497c273ac5efc65e x86/centaur: Use common IA32_FEAT_CTL MSR initialization :: TO: Sean Christopherson :: CC: Borislav Petkov --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-...@lists.01.org .config.gz Description: application/gzip
Re: [PATCH] x86/cpu: Reinitialize IA32_FEAT_CTL MSR on BSP during wakeup
Hi Sean, I love your patch! Yet something to improve: [auto build test ERROR on tip/x86/core] [also build test ERROR on tip/auto-latest v5.7 next-20200605] [cannot apply to bp/for-next] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system. BTW, we also suggest to use '--base' option to specify the base tree in git format-patch, please see https://stackoverflow.com/a/37406982] url: https://github.com/0day-ci/linux/commits/Sean-Christopherson/x86-cpu-Reinitialize-IA32_FEAT_CTL-MSR-on-BSP-during-wakeup/20200606-040921 base: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 9cb1fd0efd195590b828b9b865421ad345a4a145 config: i386-tinyconfig (attached as .config) compiler: gcc-9 (Debian 9.3.0-13) 9.3.0 reproduce (this is a W=1 build): # save the attached .config to linux build tree make W=1 ARCH=i386 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All errors (new ones prefixed by >>, old ones prefixed by <<): arch/x86/kernel/cpu/centaur.c: In function 'init_centaur': >> arch/x86/kernel/cpu/centaur.c:219:2: error: implicit declaration of function >> 'init_ia32_feat_ctl' [-Werror=implicit-function-declaration] 219 | init_ia32_feat_ctl(c); | ^~ cc1: some warnings being treated as errors -- arch/x86/kernel/cpu/zhaoxin.c: In function 'init_zhaoxin': >> arch/x86/kernel/cpu/zhaoxin.c:110:2: error: implicit declaration of function >> 'init_ia32_feat_ctl' [-Werror=implicit-function-declaration] 110 | init_ia32_feat_ctl(c); | ^~ cc1: some warnings being treated as errors vim +/init_ia32_feat_ctl +219 arch/x86/kernel/cpu/centaur.c 60882cc159e141 arch/x86/kernel/cpu/centaur.c David Wang 2018-04-20 218 501444905fcb41 arch/x86/kernel/cpu/centaur.c Sean Christopherson 2019-12-20 @219 init_ia32_feat_ctl(c); ^1da177e4c3f41 arch/i386/kernel/cpu/centaur.c Linus Torvalds 2005-04-16 220 } ^1da177e4c3f41 arch/i386/kernel/cpu/centaur.c Linus Torvalds 2005-04-16 221 :: The code at line 219 was first introduced by commit :: 501444905fcb4166589fda99497c273ac5efc65e x86/centaur: Use common IA32_FEAT_CTL MSR initialization :: TO: Sean Christopherson :: CC: Borislav Petkov --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-...@lists.01.org .config.gz Description: application/gzip
[PATCH] x86/cpu: Reinitialize IA32_FEAT_CTL MSR on BSP during wakeup
Reinitialize IA32_FEAT_CTL on the BSP during wakeup to handle the case
where firmware doesn't initialize or save/restore across S3. This fixes
a bug where IA32_FEAT_CTL is left uninitialized and results in VMXON
taking a #GP due to VMX not being fully enabled, i.e. breaks KVM.
Use init_ia32_feat_ctl() to "restore" IA32_FEAT_CTL as it already deals
with the case where the MSR is locked, and because APs already redo
init_ia32_feat_ctl() during suspend by virtue of the SMP boot flow being
used to reinitialize APs upon wakeup. Do the call in the early wakeup
flow to avoid dependencies in the syscore_ops chain, e.g. simply adding
a resume hook is not guaranteed to work, as KVM does VMXON in its own
resume hook, kvm_resume(), when KVM has active guests.
Reported-by: Brad Campbell
Cc: Maxim Levitsky
Cc: Paolo Bonzini
Cc: k...@vger.kernel.org
Fixes: 21bd3467a58e ("KVM: VMX: Drop initialization of IA32_FEAT_CTL MSR")
Signed-off-by: Sean Christopherson
---
arch/x86/include/asm/cpu.h | 5 +
arch/x86/kernel/cpu/cpu.h | 4
arch/x86/power/cpu.c | 6 ++
3 files changed, 11 insertions(+), 4 deletions(-)
diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h
index dd17c2da1af5..da78ccbd493b 100644
--- a/arch/x86/include/asm/cpu.h
+++ b/arch/x86/include/asm/cpu.h
@@ -58,4 +58,9 @@ static inline bool handle_guest_split_lock(unsigned long ip)
return false;
}
#endif
+#ifdef CONFIG_IA32_FEAT_CTL
+void init_ia32_feat_ctl(struct cpuinfo_x86 *c);
+#else
+static inline void init_ia32_feat_ctl(struct cpuinfo_x86 *c) {}
+#endif
#endif /* _ASM_X86_CPU_H */
diff --git a/arch/x86/kernel/cpu/cpu.h b/arch/x86/kernel/cpu/cpu.h
index 37fdefd14f28..38ab6e115eac 100644
--- a/arch/x86/kernel/cpu/cpu.h
+++ b/arch/x86/kernel/cpu/cpu.h
@@ -80,8 +80,4 @@ extern void x86_spec_ctrl_setup_ap(void);
extern u64 x86_read_arch_cap_msr(void);
-#ifdef CONFIG_IA32_FEAT_CTL
-void init_ia32_feat_ctl(struct cpuinfo_x86 *c);
-#endif
-
#endif /* ARCH_X86_CPU_H */
diff --git a/arch/x86/power/cpu.c b/arch/x86/power/cpu.c
index aaff9ed7ff45..b0d3c5ca6d80 100644
--- a/arch/x86/power/cpu.c
+++ b/arch/x86/power/cpu.c
@@ -193,6 +193,8 @@ static void fix_processor_context(void)
*/
static void notrace __restore_processor_state(struct saved_context *ctxt)
{
+ struct cpuinfo_x86 *c;
+
if (ctxt->misc_enable_saved)
wrmsrl(MSR_IA32_MISC_ENABLE, ctxt->misc_enable);
/*
@@ -263,6 +265,10 @@ static void notrace __restore_processor_state(struct
saved_context *ctxt)
mtrr_bp_restore();
perf_restore_debug_store();
msr_restore_context(ctxt);
+
+ c = _data(smp_processor_id());
+ if (cpu_has(c, X86_FEATURE_MSR_IA32_FEAT_CTL))
+ init_ia32_feat_ctl(c);
}
/* Needed by apm.c */
--
2.26.0
