diff options
Diffstat (limited to 'arch/arm64/kernel/vdso')
| -rw-r--r-- | arch/arm64/kernel/vdso/Makefile | 19 | ||||
| -rw-r--r-- | arch/arm64/kernel/vdso/gettimeofday.S | 22 |
2 files changed, 19 insertions, 22 deletions
diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile index b215c712d897..744b9dbaba03 100644 --- a/arch/arm64/kernel/vdso/Makefile +++ b/arch/arm64/kernel/vdso/Makefile @@ -12,17 +12,12 @@ obj-vdso := gettimeofday.o note.o sigreturn.o targets := $(obj-vdso) vdso.so vdso.so.dbg obj-vdso := $(addprefix $(obj)/, $(obj-vdso)) -ccflags-y := -shared -fno-common -fno-builtin -ccflags-y += -nostdlib -Wl,-soname=linux-vdso.so.1 \ - $(call cc-ldoption, -Wl$(comma)--hash-style=sysv) +ldflags-y := -shared -nostdlib -soname=linux-vdso.so.1 \ + $(call ld-option, --hash-style=sysv) -n -T # Disable gcov profiling for VDSO code GCOV_PROFILE := n -# Workaround for bare-metal (ELF) toolchains that neglect to pass -shared -# down to collect2, resulting in silent corruption of the vDSO image. -ccflags-y += -Wl,-shared - obj-y += vdso.o extra-y += vdso.lds CPPFLAGS_vdso.lds += -P -C -U$(ARCH) @@ -31,8 +26,8 @@ CPPFLAGS_vdso.lds += -P -C -U$(ARCH) $(obj)/vdso.o : $(obj)/vdso.so # Link rule for the .so file, .lds has to be first -$(obj)/vdso.so.dbg: $(src)/vdso.lds $(obj-vdso) - $(call if_changed,vdsold) +$(obj)/vdso.so.dbg: $(obj)/vdso.lds $(obj-vdso) FORCE + $(call if_changed,ld) # Strip rule for the .so file $(obj)/%.so: OBJCOPYFLAGS := -S @@ -42,9 +37,7 @@ $(obj)/%.so: $(obj)/%.so.dbg FORCE # Generate VDSO offsets using helper script gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh quiet_cmd_vdsosym = VDSOSYM $@ -define cmd_vdsosym - $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@ -endef + cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@ include/generated/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE $(call if_changed,vdsosym) @@ -54,8 +47,6 @@ $(obj-vdso): %.o: %.S FORCE $(call if_changed_dep,vdsoas) # Actual build commands -quiet_cmd_vdsold = VDSOL $@ - cmd_vdsold = $(CC) $(c_flags) -Wl,-n -Wl,-T $^ -o $@ quiet_cmd_vdsoas = VDSOA $@ cmd_vdsoas = $(CC) $(a_flags) -c -o $@ $< diff --git a/arch/arm64/kernel/vdso/gettimeofday.S b/arch/arm64/kernel/vdso/gettimeofday.S index c39872a7b03c..856fee6d3512 100644 --- a/arch/arm64/kernel/vdso/gettimeofday.S +++ b/arch/arm64/kernel/vdso/gettimeofday.S @@ -73,6 +73,13 @@ x_tmp .req x8 movn x_tmp, #0xff00, lsl #48 and \res, x_tmp, \res mul \res, \res, \mult + /* + * Fake address dependency from the value computed from the counter + * register to subsequent data page accesses so that the sequence + * locking also orders the read of the counter. + */ + and x_tmp, \res, xzr + add vdso_data, vdso_data, x_tmp .endm /* @@ -147,12 +154,12 @@ ENTRY(__kernel_gettimeofday) /* w11 = cs_mono_mult, w12 = cs_shift */ ldp w11, w12, [vdso_data, #VDSO_CS_MONO_MULT] ldp x13, x14, [vdso_data, #VDSO_XTIME_CLK_SEC] - seqcnt_check fail=1b get_nsec_per_sec res=x9 lsl x9, x9, x12 get_clock_shifted_nsec res=x15, cycle_last=x10, mult=x11 + seqcnt_check fail=1b get_ts_realtime res_sec=x10, res_nsec=x11, \ clock_nsec=x15, xtime_sec=x13, xtime_nsec=x14, nsec_to_sec=x9 @@ -211,13 +218,13 @@ realtime: /* w11 = cs_mono_mult, w12 = cs_shift */ ldp w11, w12, [vdso_data, #VDSO_CS_MONO_MULT] ldp x13, x14, [vdso_data, #VDSO_XTIME_CLK_SEC] - seqcnt_check fail=realtime /* All computations are done with left-shifted nsecs. */ get_nsec_per_sec res=x9 lsl x9, x9, x12 get_clock_shifted_nsec res=x15, cycle_last=x10, mult=x11 + seqcnt_check fail=realtime get_ts_realtime res_sec=x10, res_nsec=x11, \ clock_nsec=x15, xtime_sec=x13, xtime_nsec=x14, nsec_to_sec=x9 clock_gettime_return, shift=1 @@ -231,7 +238,6 @@ monotonic: ldp w11, w12, [vdso_data, #VDSO_CS_MONO_MULT] ldp x13, x14, [vdso_data, #VDSO_XTIME_CLK_SEC] ldp x3, x4, [vdso_data, #VDSO_WTM_CLK_SEC] - seqcnt_check fail=monotonic /* All computations are done with left-shifted nsecs. */ lsl x4, x4, x12 @@ -239,6 +245,7 @@ monotonic: lsl x9, x9, x12 get_clock_shifted_nsec res=x15, cycle_last=x10, mult=x11 + seqcnt_check fail=monotonic get_ts_realtime res_sec=x10, res_nsec=x11, \ clock_nsec=x15, xtime_sec=x13, xtime_nsec=x14, nsec_to_sec=x9 @@ -253,13 +260,13 @@ monotonic_raw: /* w11 = cs_raw_mult, w12 = cs_shift */ ldp w12, w11, [vdso_data, #VDSO_CS_SHIFT] ldp x13, x14, [vdso_data, #VDSO_RAW_TIME_SEC] - seqcnt_check fail=monotonic_raw /* All computations are done with left-shifted nsecs. */ get_nsec_per_sec res=x9 lsl x9, x9, x12 get_clock_shifted_nsec res=x15, cycle_last=x10, mult=x11 + seqcnt_check fail=monotonic_raw get_ts_clock_raw res_sec=x10, res_nsec=x11, \ clock_nsec=x15, nsec_to_sec=x9 @@ -301,13 +308,14 @@ ENTRY(__kernel_clock_getres) ccmp w0, #CLOCK_MONOTONIC_RAW, #0x4, ne b.ne 1f - ldr x2, 5f + adr vdso_data, _vdso_data + ldr w2, [vdso_data, #CLOCK_REALTIME_RES] b 2f 1: cmp w0, #CLOCK_REALTIME_COARSE ccmp w0, #CLOCK_MONOTONIC_COARSE, #0x4, ne b.ne 4f - ldr x2, 6f + ldr x2, 5f 2: cbz x1, 3f stp xzr, x2, [x1] @@ -321,8 +329,6 @@ ENTRY(__kernel_clock_getres) svc #0 ret 5: - .quad CLOCK_REALTIME_RES -6: .quad CLOCK_COARSE_RES .cfi_endproc ENDPROC(__kernel_clock_getres) |