Hi Cristian,
On 10/09/2019 01:04 PM, Cristian Marussi wrote:
Add some arm64/signal specific boilerplate and utility code to help further testcases' development.
Introduce also one simple testcase mangle_pstate_invalid_compat_toggle and some related helpers: it is a simple mangle testcase which messes with the ucontext_t from within the signal handler, trying to toggle PSTATE state bits to switch the system between 32bit/64bit execution state. Expects SIGSEGV on test PASS.
Reviewed-by: Dave Martin Dave.Martin@arm.com Signed-off-by: Cristian Marussi cristian.marussi@arm.com
[...]
+#define get_regval(regname, out) \ +{ \
- asm volatile("mrs %0, " __stringify(regname) \
- : "=r" (out) \
- : \
- : "memory"); \
+}
+/* Regs encoding and masks naming copied in from sysreg.h */ +#define SYS_ID_AA64MMFR1_EL1 S3_0_C0_C7_1 /* MRS Emulated */ +#define SYS_ID_AA64MMFR2_EL1 S3_0_C0_C7_2 /* MRS Emulated */ +#define ID_AA64MMFR1_PAN_SHIFT 20 +#define ID_AA64MMFR2_UAO_SHIFT 4
+/* Local Helpers */ +#define ID_AA64MMFR1_EL1_PAN_SUPPORTED(val) \
- (!!((val) & (0xfUL << ID_AA64MMFR1_PAN_SHIFT)))
+#define ID_AA64MMFR2_EL1_UAO_SUPPORTED(val) \
- (!!((val) & (0xfUL << ID_AA64MMFR2_UAO_SHIFT)))
+/*
- Feature flags used in tdescr.feats_required to specify
- any feature by the test
- */
+enum {
- FSSBS_BIT,
- FPAN_BIT,
- FUAO_BIT,
- FMAX_END
+};
+#define FEAT_SSBS (1UL << FSSBS_BIT) +#define FEAT_PAN (1UL << FPAN_BIT) +#define FEAT_UAO (1UL << FUAO_BIT)
[...]
+static int test_init(struct tdescr *td) +{
- td->minsigstksz = getauxval(AT_MINSIGSTKSZ);
- if (!td->minsigstksz)
td->minsigstksz = MINSIGSTKSZ;- fprintf(stderr, "Detected MINSTKSIGSZ:%d\n", td->minsigstksz);
- if (td->feats_required) {
td->feats_supported = 0;/** Checking for CPU required features using both the* auxval and the arm64 MRS Emulation to read sysregs.*/if (getauxval(AT_HWCAP) & HWCAP_SSBS)td->feats_supported |= FEAT_SSBS;if (getauxval(AT_HWCAP) & HWCAP_CPUID) {uint64_t val = 0;/* Uses MRS emulation to check capability */get_regval(SYS_ID_AA64MMFR1_EL1, val);if (ID_AA64MMFR1_EL1_PAN_SUPPORTED(val))td->feats_supported |= FEAT_PAN;/* Uses MRS emulation to check capability */get_regval(SYS_ID_AA64MMFR2_EL1, val);if (ID_AA64MMFR2_EL1_UAO_SUPPORTED(val))td->feats_supported |= FEAT_UAO;
As discussed, these fields are never exposed to userspace via mrs. So you may as well drop these features.
Cheers Suzuki