From d5aec90670c378b6d05e5f904b1a8c8cffb17eef Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Sat, 14 Jul 2018 02:39:30 -0700 Subject: x86/bugs: Unify x86_spec_ctrl_{set_guest, restore_host} commit cc69b34989210f067b2c51d5539b5f96ebcc3a01 upstream Function bodies are very similar and are going to grow more almost identical code. Add a bool arg to determine whether SPEC_CTRL is being set for the guest or restored to the host. No functional changes. Signed-off-by: Borislav Petkov Signed-off-by: Thomas Gleixner Reviewed-by: Konrad Rzeszutek Wilk Signed-off-by: David Woodhouse Signed-off-by: Greg Kroah-Hartman Signed-off-by: Srivatsa S. Bhat Reviewed-by: Matt Helsley (VMware) Reviewed-by: Alexey Makhalov Reviewed-by: Bo Gan Signed-off-by: Greg Kroah-Hartman --- arch/x86/include/asm/spec-ctrl.h | 33 +++++++++++++++++++--- arch/x86/kernel/cpu/bugs.c | 60 ++++++++++------------------------------ 2 files changed, 44 insertions(+), 49 deletions(-) diff --git a/arch/x86/include/asm/spec-ctrl.h b/arch/x86/include/asm/spec-ctrl.h index 82b6c5a0d61e..9cecbe5e57ee 100644 --- a/arch/x86/include/asm/spec-ctrl.h +++ b/arch/x86/include/asm/spec-ctrl.h @@ -13,10 +13,35 @@ * Takes the guest view of SPEC_CTRL MSR as a parameter and also * the guest's version of VIRT_SPEC_CTRL, if emulated. */ -extern void x86_spec_ctrl_set_guest(u64 guest_spec_ctrl, - u64 guest_virt_spec_ctrl); -extern void x86_spec_ctrl_restore_host(u64 guest_spec_ctrl, - u64 guest_virt_spec_ctrl); +extern void x86_virt_spec_ctrl(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl, bool guest); + +/** + * x86_spec_ctrl_set_guest - Set speculation control registers for the guest + * @guest_spec_ctrl: The guest content of MSR_SPEC_CTRL + * @guest_virt_spec_ctrl: The guest controlled bits of MSR_VIRT_SPEC_CTRL + * (may get translated to MSR_AMD64_LS_CFG bits) + * + * Avoids writing to the MSR if the content/bits are the same + */ +static inline +void x86_spec_ctrl_set_guest(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl) +{ + x86_virt_spec_ctrl(guest_spec_ctrl, guest_virt_spec_ctrl, true); +} + +/** + * x86_spec_ctrl_restore_host - Restore host speculation control registers + * @guest_spec_ctrl: The guest content of MSR_SPEC_CTRL + * @guest_virt_spec_ctrl: The guest controlled bits of MSR_VIRT_SPEC_CTRL + * (may get translated to MSR_AMD64_LS_CFG bits) + * + * Avoids writing to the MSR if the content/bits are the same + */ +static inline +void x86_spec_ctrl_restore_host(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl) +{ + x86_virt_spec_ctrl(guest_spec_ctrl, guest_virt_spec_ctrl, false); +} /* AMD specific Speculative Store Bypass MSR data */ extern u64 x86_amd_ls_cfg_base; diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 1b29be9211af..208d44c5cc50 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -149,55 +149,25 @@ u64 x86_spec_ctrl_get_default(void) } EXPORT_SYMBOL_GPL(x86_spec_ctrl_get_default); -/** - * x86_spec_ctrl_set_guest - Set speculation control registers for the guest - * @guest_spec_ctrl: The guest content of MSR_SPEC_CTRL - * @guest_virt_spec_ctrl: The guest controlled bits of MSR_VIRT_SPEC_CTRL - * (may get translated to MSR_AMD64_LS_CFG bits) - * - * Avoids writing to the MSR if the content/bits are the same - */ -void x86_spec_ctrl_set_guest(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl) +void +x86_virt_spec_ctrl(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl, bool setguest) { - u64 host = x86_spec_ctrl_base; + struct thread_info *ti = current_thread_info(); + u64 msr, host = x86_spec_ctrl_base; /* Is MSR_SPEC_CTRL implemented ? */ - if (!static_cpu_has(X86_FEATURE_MSR_SPEC_CTRL)) - return; - - /* SSBD controlled in MSR_SPEC_CTRL */ - if (static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD)) - host |= ssbd_tif_to_spec_ctrl(current_thread_info()->flags); - - if (host != guest_spec_ctrl) - wrmsrl(MSR_IA32_SPEC_CTRL, guest_spec_ctrl); -} -EXPORT_SYMBOL_GPL(x86_spec_ctrl_set_guest); - -/** - * x86_spec_ctrl_restore_host - Restore host speculation control registers - * @guest_spec_ctrl: The guest content of MSR_SPEC_CTRL - * @guest_virt_spec_ctrl: The guest controlled bits of MSR_VIRT_SPEC_CTRL - * (may get translated to MSR_AMD64_LS_CFG bits) - * - * Avoids writing to the MSR if the content/bits are the same - */ -void x86_spec_ctrl_restore_host(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl) -{ - u64 host = x86_spec_ctrl_base; - - /* Is MSR_SPEC_CTRL implemented ? */ - if (!static_cpu_has(X86_FEATURE_MSR_SPEC_CTRL)) - return; - - /* SSBD controlled in MSR_SPEC_CTRL */ - if (static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD)) - host |= ssbd_tif_to_spec_ctrl(current_thread_info()->flags); - - if (host != guest_spec_ctrl) - wrmsrl(MSR_IA32_SPEC_CTRL, host); + if (static_cpu_has(X86_FEATURE_MSR_SPEC_CTRL)) { + /* SSBD controlled in MSR_SPEC_CTRL */ + if (static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD)) + host |= ssbd_tif_to_spec_ctrl(ti->flags); + + if (host != guest_spec_ctrl) { + msr = setguest ? guest_spec_ctrl : host; + wrmsrl(MSR_IA32_SPEC_CTRL, msr); + } + } } -EXPORT_SYMBOL_GPL(x86_spec_ctrl_restore_host); +EXPORT_SYMBOL_GPL(x86_virt_spec_ctrl); static void x86_amd_ssb_disable(void) { -- cgit v1.2.3