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-rw-r--r--arch/x86/entry/vdso/vclock_gettime.c25
-rw-r--r--arch/x86/entry/vdso/vdso2c.h6
2 files changed, 11 insertions, 20 deletions
diff --git a/arch/x86/entry/vdso/vclock_gettime.c b/arch/x86/entry/vdso/vclock_gettime.c
index 2f02d23a05ef..94d54d0defa7 100644
--- a/arch/x86/entry/vdso/vclock_gettime.c
+++ b/arch/x86/entry/vdso/vclock_gettime.c
@@ -96,9 +96,8 @@ static notrace cycle_t vread_pvclock(int *mode)
{
const struct pvclock_vcpu_time_info *pvti = &get_pvti0()->pvti;
cycle_t ret;
- u64 tsc, pvti_tsc;
- u64 last, delta, pvti_system_time;
- u32 version, pvti_tsc_to_system_mul, pvti_tsc_shift;
+ u64 last;
+ u32 version;
/*
* Note: The kernel and hypervisor must guarantee that cpu ID
@@ -123,29 +122,15 @@ static notrace cycle_t vread_pvclock(int *mode)
*/
do {
- version = pvti->version;
-
- smp_rmb();
+ version = pvclock_read_begin(pvti);
if (unlikely(!(pvti->flags & PVCLOCK_TSC_STABLE_BIT))) {
*mode = VCLOCK_NONE;
return 0;
}
- tsc = rdtsc_ordered();
- pvti_tsc_to_system_mul = pvti->tsc_to_system_mul;
- pvti_tsc_shift = pvti->tsc_shift;
- pvti_system_time = pvti->system_time;
- pvti_tsc = pvti->tsc_timestamp;
-
- /* Make sure that the version double-check is last. */
- smp_rmb();
- } while (unlikely((version & 1) || version != pvti->version));
-
- delta = tsc - pvti_tsc;
- ret = pvti_system_time +
- pvclock_scale_delta(delta, pvti_tsc_to_system_mul,
- pvti_tsc_shift);
+ ret = __pvclock_read_cycles(pvti);
+ } while (pvclock_read_retry(pvti, version));
/* refer to vread_tsc() comment for rationale */
last = gtod->cycle_last;
diff --git a/arch/x86/entry/vdso/vdso2c.h b/arch/x86/entry/vdso/vdso2c.h
index 63a03bb91497..4f741192846d 100644
--- a/arch/x86/entry/vdso/vdso2c.h
+++ b/arch/x86/entry/vdso/vdso2c.h
@@ -22,6 +22,9 @@ static void BITSFUNC(go)(void *raw_addr, size_t raw_len,
ELF(Phdr) *pt = (ELF(Phdr) *)(raw_addr + GET_LE(&hdr->e_phoff));
+ if (hdr->e_type != ET_DYN)
+ fail("input is not a shared object\n");
+
/* Walk the segment table. */
for (i = 0; i < GET_LE(&hdr->e_phnum); i++) {
if (GET_LE(&pt[i].p_type) == PT_LOAD) {
@@ -49,6 +52,9 @@ static void BITSFUNC(go)(void *raw_addr, size_t raw_len,
if (stripped_len < load_size)
fail("stripped input is too short\n");
+ if (!dyn)
+ fail("input has no PT_DYNAMIC section -- your toolchain is buggy\n");
+
/* Walk the dynamic table */
for (i = 0; dyn + i < dyn_end &&
GET_LE(&dyn[i].d_tag) != DT_NULL; i++) {