[PATCH 0/2] riscv: stack: Fixup independent softirq/irq stack for CONFIG_FRAME_POINTER=n
From: Guo Ren guoren@linux.alibaba.com
The independent softirq/irq stack uses s0 to save & restore sp, but s0 would be corrupted when CONFIG_FRAME_POINTER=n. So add s0 in the clobber list to fix the problem.
<+0>: addi sp,sp,-32 <+2>: sd s0,16(sp) <+4>: sd s1,8(sp) <+6>: sd ra,24(sp) <+8>: sd s2,0(sp) <+10>: mv s0,a0 --> compiler allocate s0 for a0 when CONFIG_FRAME_POINTER=n <+12>: jal ra,0xffffffff800bc0ce <irqentry_enter> <+16>: ld a5,56(tp) # 0x38 <+20>: lui a4,0x4 <+22>: mv s1,a0 <+24>: xor a5,a5,sp <+28>: bgeu a5,a4,0xffffffff800bc092 <do_irq+88> <+32>: auipc s2,0x5d <+36>: ld s2,1118(s2) # 0xffffffff801194b8 <irq_stack_ptr> <+40>: add s2,s2,a4 <+42>: addi sp,sp,-8 <+44>: sd ra,0(sp) <+46>: addi sp,sp,-8 <+48>: sd s0,0(sp) <+50>: addi s0,sp,16 --> our code clobber the s0 <+52>: mv sp,s2 <+54>: mv a0,s0 --> a0 got wrong value for handle_riscv_irq <+56>: jal ra,0xffffffff800bbb3a <handle_riscv_irq>
Guo Ren (2): riscv: stack: Fixup independent irq stack for CONFIG_FRAME_POINTER=n riscv: stack: Fixup independent softirq stack for CONFIG_FRAME_POINTER=n
arch/riscv/kernel/irq.c | 2 +- arch/riscv/kernel/traps.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
From: Guo Ren guoren@linux.alibaba.com
The independent irq stack uses s0 to save & restore sp, but s0 would be corrupted when CONFIG_FRAME_POINTER=n. So add s0 in the clobber list to fix the problem.
Fixes: 163e76cc6ef4 ("riscv: stack: Support HAVE_IRQ_EXIT_ON_IRQ_STACK") Reported-by: Zhangjin Wu falcon@tinylab.org Signed-off-by: Guo Ren guoren@linux.alibaba.com Signed-off-by: Guo Ren guoren@kernel.org --- arch/riscv/kernel/traps.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c index f910dfccbf5d..f75d97de518a 100644 --- a/arch/riscv/kernel/traps.c +++ b/arch/riscv/kernel/traps.c @@ -371,7 +371,7 @@ asmlinkage void noinstr do_irq(struct pt_regs *regs) : : [sp] "r" (sp), [regs] "r" (regs) : "a0", "a1", "a2", "a3", "a4", "a5", "a6", "a7", - "t0", "t1", "t2", "t3", "t4", "t5", "t6", + "t0", "t1", "t2", "t3", "t4", "t5", "t6", "s0", "memory"); } else #endif
Hi,
Thanks for your patch.
FYI: kernel test robot notices the stable kernel rule is not satisfied.
Rule: 'Cc: stable@vger.kernel.org' or 'commit <sha1> upstream.' Subject: [PATCH 1/2] riscv: stack: Fixup independent irq stack for CONFIG_FRAME_POINTER=n Link: https://lore.kernel.org/stable/20230715134552.3437933-2-guoren%40kernel.org
The check is based on https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
From: Guo Ren guoren@linux.alibaba.com
The independent softirq stack uses s0 to save & restore sp, but s0 would be corrupted when CONFIG_FRAME_POINTER=n. So add s0 in the clobber list to fix the problem.
Fixes: dd69d07a5a6c ("riscv: stack: Support HAVE_SOFTIRQ_ON_OWN_STACK") Reported-by: Zhangjin Wu falcon@tinylab.org Signed-off-by: Guo Ren guoren@linux.alibaba.com Signed-off-by: Guo Ren guoren@kernel.org --- arch/riscv/kernel/irq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/riscv/kernel/irq.c b/arch/riscv/kernel/irq.c index d0577cc6a081..0b58720109db 100644 --- a/arch/riscv/kernel/irq.c +++ b/arch/riscv/kernel/irq.c @@ -83,7 +83,7 @@ void do_softirq_own_stack(void) : : [sp] "r" (sp) : "a0", "a1", "a2", "a3", "a4", "a5", "a6", "a7", - "t0", "t1", "t2", "t3", "t4", "t5", "t6", + "t0", "t1", "t2", "t3", "t4", "t5", "t6", "s0", "memory"); } else #endif
On Sat, Jul 15, 2023 at 09:45:52AM -0400, guoren@kernel.org wrote:
From: Guo Ren guoren@linux.alibaba.com
The independent softirq stack uses s0 to save & restore sp, but s0 would be corrupted when CONFIG_FRAME_POINTER=n. So add s0 in the clobber list to fix the problem.
Fixes: dd69d07a5a6c ("riscv: stack: Support HAVE_SOFTIRQ_ON_OWN_STACK") Reported-by: Zhangjin Wu falcon@tinylab.org Signed-off-by: Guo Ren guoren@linux.alibaba.com Signed-off-by: Guo Ren guoren@kernel.org
arch/riscv/kernel/irq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/riscv/kernel/irq.c b/arch/riscv/kernel/irq.c index d0577cc6a081..0b58720109db 100644 --- a/arch/riscv/kernel/irq.c +++ b/arch/riscv/kernel/irq.c @@ -83,7 +83,7 @@ void do_softirq_own_stack(void) : : [sp] "r" (sp) : "a0", "a1", "a2", "a3", "a4", "a5", "a6", "a7",
"t0", "t1", "t2", "t3", "t4", "t5", "t6",
"t0", "t1", "t2", "t3", "t4", "t5", "t6", "s0",#endif
2.36.1
<formletter>
This is not the correct way to submit patches for inclusion in the stable kernel tree. Please read: https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html for how to do this properly.
</formletter>
I'm sorry, this patch would break CONFIG_FRAME_POINTER=y, so please abandon it.
I've updated a v2 with the stable@ver.kernel.org tag fixed: https://lore.kernel.org/linux-riscv/20230716001506.3506041-1-guoren@kernel.o...
On Sat, Jul 15, 2023 at 9:46 PM guoren@kernel.org wrote:
From: Guo Ren guoren@linux.alibaba.com
The independent softirq/irq stack uses s0 to save & restore sp, but s0 would be corrupted when CONFIG_FRAME_POINTER=n. So add s0 in the clobber list to fix the problem.
<+0>: addi sp,sp,-32 <+2>: sd s0,16(sp) <+4>: sd s1,8(sp) <+6>: sd ra,24(sp) <+8>: sd s2,0(sp) <+10>: mv s0,a0 --> compiler allocate s0 for a0 when CONFIG_FRAME_POINTER=n <+12>: jal ra,0xffffffff800bc0ce <irqentry_enter> <+16>: ld a5,56(tp) # 0x38 <+20>: lui a4,0x4 <+22>: mv s1,a0 <+24>: xor a5,a5,sp <+28>: bgeu a5,a4,0xffffffff800bc092 <do_irq+88> <+32>: auipc s2,0x5d <+36>: ld s2,1118(s2) # 0xffffffff801194b8 <irq_stack_ptr> <+40>: add s2,s2,a4 <+42>: addi sp,sp,-8 <+44>: sd ra,0(sp) <+46>: addi sp,sp,-8 <+48>: sd s0,0(sp) <+50>: addi s0,sp,16 --> our code clobber the s0 <+52>: mv sp,s2 <+54>: mv a0,s0 --> a0 got wrong value for handle_riscv_irq <+56>: jal ra,0xffffffff800bbb3a <handle_riscv_irq>
Guo Ren (2): riscv: stack: Fixup independent irq stack for CONFIG_FRAME_POINTER=n riscv: stack: Fixup independent softirq stack for CONFIG_FRAME_POINTER=n
arch/riscv/kernel/irq.c | 2 +- arch/riscv/kernel/traps.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
-- 2.36.1
-- Best Regards
Guo Ren
linux-stable-mirror@lists.linaro.org
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Greg KH -
Guo Ren -
guoren＠kernel.org
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kernel test robot