Add support to enforce access tests to be handled by the emulator, if supported by KVM. Exclude it from the ac_test_exec() test, though, to not slow it down too much. Signed-off-by: Mathias Krause <minipli@xxxxxxxxxxxxxx> --- x86/access.c | 37 ++++++++++++++++++++++++++++++++----- 1 file changed, 32 insertions(+), 5 deletions(-) diff --git a/x86/access.c b/x86/access.c index d1ec99b4fa73..ae5e7d8e8892 100644 --- a/x86/access.c +++ b/x86/access.c @@ -82,6 +82,13 @@ enum { AC_CPU_CR4_SMEP_BIT, AC_CPU_CR4_PKE_BIT, + NR_AC_TEST_FLAGS, + + /* + * synthetic flags follow, won't be exercised by ac_test_exec(). + */ + AC_FEP_BIT, + NR_AC_FLAGS }; @@ -121,6 +128,8 @@ enum { #define AC_CPU_CR4_SMEP_MASK (1 << AC_CPU_CR4_SMEP_BIT) #define AC_CPU_CR4_PKE_MASK (1 << AC_CPU_CR4_PKE_BIT) +#define AC_FEP_MASK (1 << AC_FEP_BIT) + const char *ac_names[] = { [AC_PTE_PRESENT_BIT] = "pte.p", [AC_PTE_ACCESSED_BIT] = "pte.a", @@ -152,6 +161,7 @@ const char *ac_names[] = { [AC_CPU_CR0_WP_BIT] = "cr0.wp", [AC_CPU_CR4_SMEP_BIT] = "cr4.smep", [AC_CPU_CR4_PKE_BIT] = "cr4.pke", + [AC_FEP_BIT] = "fep", }; static inline void *va(pt_element_t phys) @@ -190,6 +200,7 @@ typedef struct { static void ac_test_show(ac_test_t *at); +static bool fep_available; static unsigned long shadow_cr0; static unsigned long shadow_cr3; static unsigned long shadow_cr4; @@ -396,7 +407,7 @@ static void ac_test_init(ac_test_t *at, unsigned long virt, ac_pt_env_t *pt_env) static int ac_test_bump_one(ac_test_t *at) { at->flags = ((at->flags | invalid_mask) + 1) & ~invalid_mask; - return at->flags < (1 << NR_AC_FLAGS); + return at->flags < (1 << NR_AC_TEST_FLAGS); } #define F(x) ((flags & x##_MASK) != 0) @@ -799,10 +810,13 @@ static int ac_test_do_access(ac_test_t *at) if (F(AC_ACCESS_TWICE)) { asm volatile ("mov $fixed2, %%rsi \n\t" - "mov (%[addr]), %[reg] \n\t" + "cmp $0, %[fep] \n\t" + "jz 1f \n\t" + KVM_FEP + "1: mov (%[addr]), %[reg] \n\t" "fixed2:" : [reg]"=r"(r), [fault]"=a"(fault), "=b"(e) - : [addr]"r"(at->virt) + : [addr]"r"(at->virt), [fep]"r"(F(AC_FEP)) : "rsi"); fault = 0; } @@ -823,9 +837,15 @@ static int ac_test_do_access(ac_test_t *at) "jnz 2f \n\t" "cmp $0, %[write] \n\t" "jnz 1f \n\t" - "mov (%[addr]), %[reg] \n\t" + "cmp $0, %[fep] \n\t" + "jz 0f \n\t" + KVM_FEP + "0: mov (%[addr]), %[reg] \n\t" "jmp done \n\t" - "1: mov %[reg], (%[addr]) \n\t" + "1: cmp $0, %[fep] \n\t" + "jz 0f \n\t" + KVM_FEP + "0: mov %[reg], (%[addr]) \n\t" "jmp done \n\t" "2: call *%[addr] \n\t" "done: \n" @@ -843,6 +863,7 @@ static int ac_test_do_access(ac_test_t *at) [write]"r"(F(AC_ACCESS_WRITE)), [user]"r"(F(AC_ACCESS_USER)), [fetch]"r"(F(AC_ACCESS_FETCH)), + [fep]"r"(F(AC_FEP)), [user_ds]"i"(USER_DS), [user_cs]"i"(USER_CS), [user_stack_top]"r"(user_stack + sizeof user_stack), @@ -1228,6 +1249,12 @@ int ac_test_run(int pt_levels) invalid_mask |= AC_PTE_BIT36_MASK; } + fep_available = is_fep_available(); + if (!fep_available) { + printf("FEP not available, skipping emulation tests\n"); + invalid_mask |= AC_FEP_MASK; + } + ac_env_int(&pt_env, pt_levels); ac_test_init(&at, 0xffff923400000000ul, &pt_env); -- 2.39.2