e05d57dcb8
For linux-5.8-rc1, enable ftrace of riscv will cause boot panic:
[ 2.388980] Run /sbin/init as init process
[ 2.529938] init[39]: unhandled signal 4 code 0x1 at 0x0000003ff449e000
[ 2.531078] CPU: 0 PID: 39 Comm: init Not tainted 5.8.0-rc1-dirty #13
[ 2.532719] epc: 0000003ff449e000 ra : 0000003ff449e954 sp : 0000003fffedb900
[ 2.534005] gp : 00000000000e8528 tp : 0000003ff449d800 t0 : 000000000000001e
[ 2.534965] t1 : 000000000000000a t2 : 0000003fffedb89e s0 : 0000003fffedb920
[ 2.536279] s1 : 0000003fffedb940 a0 : 0000003ff43d4b2c a1 : 0000000000000000
[ 2.537334] a2 : 0000000000000001 a3 : 0000000000000000 a4 : fffffffffbad8000
[ 2.538466] a5 : 0000003ff449e93a a6 : 0000000000000000 a7 : 0000000000000000
[ 2.539511] s2 : 0000000000000000 s3 : 0000003ff448412c s4 : 0000000000000010
[ 2.541260] s5 : 0000000000000016 s6 : 00000000000d0a30 s7 : 0000003fffedba70
[ 2.542152] s8 : 0000000000000000 s9 : 0000000000000000 s10: 0000003fffedb960
[ 2.543335] s11: 0000000000000000 t3 : 0000000000000000 t4 : 0000003fffedb8a0
[ 2.544471] t5 : 0000000000000000 t6 : 0000000000000000
[ 2.545730] status: 0000000000004020 badaddr: 00000000464c457f cause: 0000000000000002
[ 2.549867] Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000004
[ 2.551267] CPU: 0 PID: 1 Comm: init Not tainted 5.8.0-rc1-dirty #13
[ 2.552061] Call Trace:
[ 2.552626] [<ffffffe00020374a>] walk_stackframe+0x0/0xc4
[ 2.553486] [<ffffffe0002039f4>] show_stack+0x40/0x4c
[ 2.553995] [<ffffffe00054a6ae>] dump_stack+0x7a/0x98
[ 2.554615] [<ffffffe00020b9b8>] panic+0x114/0x2f4
[ 2.555395] [<ffffffe00020ebd6>] do_exit+0x89c/0x8c2
[ 2.555949] [<ffffffe00020f930>] do_group_exit+0x3a/0x90
[ 2.556715] [<ffffffe000219e08>] get_signal+0xe2/0x6e6
[ 2.557388] [<ffffffe000202d72>] do_notify_resume+0x6a/0x37a
[ 2.558089] [<ffffffe000201c16>] ret_from_exception+0x0/0xc
"ra:0x3ff449e954" is the return address of "call _mcount" in the
prologue of __vdso_gettimeofday(). Without proper relocate, pc jmp
to 0x0000003ff449e000 (vdso map base) with a illegal instruction
trap.
The solution comes from arch/arm64/kernel/vdso/Makefile:
CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os $(CC_FLAGS_SCS)
- CC_FLAGS_SCS is ShadowCallStack feature in Clang and only
implemented for arm64, no use for riscv.
Fixes: ad5d1122b8 ("riscv: use vDSO common flow to reduce the latency of the time-related functions")
Cc: stable@vger.kernel.org
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Reviewed-by: Vincent Chen <vincent.chen@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
82 lines
2.6 KiB
Makefile
82 lines
2.6 KiB
Makefile
# SPDX-License-Identifier: GPL-2.0-only
|
|
# Copied from arch/tile/kernel/vdso/Makefile
|
|
|
|
# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
|
|
# the inclusion of generic Makefile.
|
|
ARCH_REL_TYPE_ABS := R_RISCV_32|R_RISCV_64|R_RISCV_JUMP_SLOT
|
|
include $(srctree)/lib/vdso/Makefile
|
|
# Symbols present in the vdso
|
|
vdso-syms = rt_sigreturn
|
|
ifdef CONFIG_64BIT
|
|
vdso-syms += vgettimeofday
|
|
endif
|
|
vdso-syms += getcpu
|
|
vdso-syms += flush_icache
|
|
|
|
# Files to link into the vdso
|
|
obj-vdso = $(patsubst %, %.o, $(vdso-syms)) note.o
|
|
|
|
ifneq ($(c-gettimeofday-y),)
|
|
CFLAGS_vgettimeofday.o += -fPIC -include $(c-gettimeofday-y)
|
|
endif
|
|
|
|
# Build rules
|
|
targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.lds vdso-dummy.o
|
|
obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
|
|
|
|
obj-y += vdso.o vdso-syms.o
|
|
CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
|
|
|
|
# Disable -pg to prevent insert call site
|
|
CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os
|
|
|
|
# Disable gcov profiling for VDSO code
|
|
GCOV_PROFILE := n
|
|
|
|
# Force dependency
|
|
$(obj)/vdso.o: $(obj)/vdso.so
|
|
|
|
# link rule for the .so file, .lds has to be first
|
|
SYSCFLAGS_vdso.so.dbg = $(c_flags)
|
|
$(obj)/vdso.so.dbg: $(src)/vdso.lds $(obj-vdso) FORCE
|
|
$(call if_changed,vdsold)
|
|
|
|
# We also create a special relocatable object that should mirror the symbol
|
|
# table and layout of the linked DSO. With ld --just-symbols we can then
|
|
# refer to these symbols in the kernel code rather than hand-coded addresses.
|
|
|
|
SYSCFLAGS_vdso.so.dbg = -shared -s -Wl,-soname=linux-vdso.so.1 \
|
|
-Wl,--build-id -Wl,--hash-style=both
|
|
$(obj)/vdso-dummy.o: $(src)/vdso.lds $(obj)/rt_sigreturn.o FORCE
|
|
$(call if_changed,vdsold)
|
|
|
|
LDFLAGS_vdso-syms.o := -r --just-symbols
|
|
$(obj)/vdso-syms.o: $(obj)/vdso-dummy.o FORCE
|
|
$(call if_changed,ld)
|
|
|
|
# strip rule for the .so file
|
|
$(obj)/%.so: OBJCOPYFLAGS := -S
|
|
$(obj)/%.so: $(obj)/%.so.dbg FORCE
|
|
$(call if_changed,objcopy)
|
|
|
|
# actual build commands
|
|
# The DSO images are built using a special linker script
|
|
# Add -lgcc so rv32 gets static muldi3 and lshrdi3 definitions.
|
|
# Make sure only to export the intended __vdso_xxx symbol offsets.
|
|
quiet_cmd_vdsold = VDSOLD $@
|
|
cmd_vdsold = $(CC) $(KBUILD_CFLAGS) $(call cc-option, -no-pie) -nostdlib -nostartfiles $(SYSCFLAGS_$(@F)) \
|
|
-Wl,-T,$(filter-out FORCE,$^) -o $@.tmp && \
|
|
$(CROSS_COMPILE)objcopy \
|
|
$(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@ && \
|
|
rm $@.tmp
|
|
|
|
# install commands for the unstripped file
|
|
quiet_cmd_vdso_install = INSTALL $@
|
|
cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
|
|
|
|
vdso.so: $(obj)/vdso.so.dbg
|
|
@mkdir -p $(MODLIB)/vdso
|
|
$(call cmd,vdso_install)
|
|
|
|
vdso_install: vdso.so
|