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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-03-04 11:40:16 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-03-04 11:40:16 -0800 |
| commit | 7225a442788e20ee108ef2cb97d511375e20acf9 (patch) | |
| tree | 98b2ecf1b606bd843356a8df7826a2e1c78d1eca /arch/x86/xen | |
| parent | 4c4ce3022dc7352d05de4d8e1602c9a2a14458bf (diff) | |
| parent | 945fd17ab6bab8a4d05da6c3170519fbcfe62ddb (diff) | |
Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86/pti fixes from Thomas Gleixner:
"Three fixes related to melted spectrum:
- Sync the cpu_entry_area page table to initial_page_table on 32 bit.
Otherwise suspend/resume fails because resume uses
initial_page_table and triggers a triple fault when accessing the
cpu entry area.
- Zero the SPEC_CTL MRS on XEN before suspend to address a
shortcoming in the hypervisor.
- Fix another switch table detection issue in objtool"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpu_entry_area: Sync cpu_entry_area to initial_page_table
objtool: Fix another switch table detection issue
x86/xen: Zero MSR_IA32_SPEC_CTRL before suspend
Diffstat (limited to 'arch/x86/xen')
| -rw-r--r-- | arch/x86/xen/suspend.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/arch/x86/xen/suspend.c b/arch/x86/xen/suspend.c index d9f96cc5d743..1d83152c761b 100644 --- a/arch/x86/xen/suspend.c +++ b/arch/x86/xen/suspend.c @@ -1,12 +1,15 @@ // SPDX-License-Identifier: GPL-2.0 #include <linux/types.h> #include <linux/tick.h> +#include <linux/percpu-defs.h> #include <xen/xen.h> #include <xen/interface/xen.h> #include <xen/grant_table.h> #include <xen/events.h> +#include <asm/cpufeatures.h> +#include <asm/msr-index.h> #include <asm/xen/hypercall.h> #include <asm/xen/page.h> #include <asm/fixmap.h> @@ -15,6 +18,8 @@ #include "mmu.h" #include "pmu.h" +static DEFINE_PER_CPU(u64, spec_ctrl); + void xen_arch_pre_suspend(void) { xen_save_time_memory_area(); @@ -35,6 +40,9 @@ void xen_arch_post_suspend(int cancelled) static void xen_vcpu_notify_restore(void *data) { + if (xen_pv_domain() && boot_cpu_has(X86_FEATURE_SPEC_CTRL)) + wrmsrl(MSR_IA32_SPEC_CTRL, this_cpu_read(spec_ctrl)); + /* Boot processor notified via generic timekeeping_resume() */ if (smp_processor_id() == 0) return; @@ -44,7 +52,15 @@ static void xen_vcpu_notify_restore(void *data) static void xen_vcpu_notify_suspend(void *data) { + u64 tmp; + tick_suspend_local(); + + if (xen_pv_domain() && boot_cpu_has(X86_FEATURE_SPEC_CTRL)) { + rdmsrl(MSR_IA32_SPEC_CTRL, tmp); + this_cpu_write(spec_ctrl, tmp); + wrmsrl(MSR_IA32_SPEC_CTRL, 0); + } } void xen_arch_resume(void) |