From: Joerg Roedel <[email protected]> This patch introduces a list with all msrs a guest might have direct access to and changes the svm_vcpu_init_msrpm function to use this list. It also adds a check to set_msr_interception which triggers a warning if a developer changes a msr intercept that is not in the list.
Signed-off-by: Joerg Roedel <[email protected]> Signed-off-by: Marcelo Tosatti <[email protected]> diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index c0c01a8..18d7938 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -118,6 +118,27 @@ struct vcpu_svm { #define MSR_INVALID 0xffffffffU +static struct svm_direct_access_msrs { + u32 index; /* Index of the MSR */ + bool always; /* True if intercept is always on */ +} direct_access_msrs[] = { + { .index = MSR_K6_STAR, .always = true }, + { .index = MSR_IA32_SYSENTER_CS, .always = true }, +#ifdef CONFIG_X86_64 + { .index = MSR_GS_BASE, .always = true }, + { .index = MSR_FS_BASE, .always = true }, + { .index = MSR_KERNEL_GS_BASE, .always = true }, + { .index = MSR_LSTAR, .always = true }, + { .index = MSR_CSTAR, .always = true }, + { .index = MSR_SYSCALL_MASK, .always = true }, +#endif + { .index = MSR_IA32_LASTBRANCHFROMIP, .always = false }, + { .index = MSR_IA32_LASTBRANCHTOIP, .always = false }, + { .index = MSR_IA32_LASTINTFROMIP, .always = false }, + { .index = MSR_IA32_LASTINTTOIP, .always = false }, + { .index = MSR_INVALID, .always = false }, +}; + /* enable NPT for AMD64 and X86 with PAE */ #if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE) static bool npt_enabled = true; @@ -437,6 +458,17 @@ err_1: } +static bool valid_msr_intercept(u32 index) +{ + int i; + + for (i = 0; direct_access_msrs[i].index != MSR_INVALID; i++) + if (direct_access_msrs[i].index == index) + return true; + + return false; +} + static void set_msr_interception(u32 *msrpm, unsigned msr, int read, int write) { @@ -444,6 +476,12 @@ static void set_msr_interception(u32 *msrpm, unsigned msr, unsigned long tmp; u32 offset; + /* + * If this warning triggers extend the direct_access_msrs list at the + * beginning of the file + */ + WARN_ON(!valid_msr_intercept(msr)); + offset = svm_msrpm_offset(msr); bit_read = 2 * (msr & 0x0f); bit_write = 2 * (msr & 0x0f) + 1; @@ -459,18 +497,16 @@ static void set_msr_interception(u32 *msrpm, unsigned msr, static void svm_vcpu_init_msrpm(u32 *msrpm) { + int i; + memset(msrpm, 0xff, PAGE_SIZE * (1 << MSRPM_ALLOC_ORDER)); -#ifdef CONFIG_X86_64 - set_msr_interception(msrpm, MSR_GS_BASE, 1, 1); - set_msr_interception(msrpm, MSR_FS_BASE, 1, 1); - set_msr_interception(msrpm, MSR_KERNEL_GS_BASE, 1, 1); - set_msr_interception(msrpm, MSR_LSTAR, 1, 1); - set_msr_interception(msrpm, MSR_CSTAR, 1, 1); - set_msr_interception(msrpm, MSR_SYSCALL_MASK, 1, 1); -#endif - set_msr_interception(msrpm, MSR_K6_STAR, 1, 1); - set_msr_interception(msrpm, MSR_IA32_SYSENTER_CS, 1, 1); + for (i = 0; direct_access_msrs[i].index != MSR_INVALID; i++) { + if (!direct_access_msrs[i].always) + continue; + + set_msr_interception(msrpm, direct_access_msrs[i].index, 1, 1); + } } static void svm_enable_lbrv(struct vcpu_svm *svm) -- To unsubscribe from this list: send the line "unsubscribe kvm-commits" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
