From b6621895b488ba6c81f40d516d2da281f22738cc Mon Sep 17 00:00:00 2001 From: Max Filippov Date: Sat, 17 Feb 2024 05:15:42 -0800 Subject: [PATCH] xtensa: fix MAKE_PC_FROM_RA second argument [ Upstream commit 0e60f0b75884677fb9f4f2ad40d52b43451564d5 ] Xtensa has two-argument MAKE_PC_FROM_RA macro to convert a0 to an actual return address because when windowed ABI is used call{,x}{4,8,12} opcodes stuff encoded window size into the top 2 bits of the register that becomes a return address in the called function. Second argument of that macro is supposed to be an address having these 2 topmost bits set correctly, but the comment suggested that that could be the stack address. However the stack doesn't have to be in the same 1GByte region as the code, especially in noMMU XIP configurations. Fix the comment and use either _text or regs->pc as the second argument for the MAKE_PC_FROM_RA macro. Cc: stable@vger.kernel.org Signed-off-by: Max Filippov Signed-off-by: Sasha Levin --- arch/xtensa/include/asm/processor.h | 8 ++++---- arch/xtensa/include/asm/ptrace.h | 2 +- arch/xtensa/kernel/process.c | 5 +++-- arch/xtensa/kernel/stacktrace.c | 3 ++- 4 files changed, 10 insertions(+), 8 deletions(-) diff --git a/arch/xtensa/include/asm/processor.h b/arch/xtensa/include/asm/processor.h index 228e4dff5fb2..ab555a980147 100644 --- a/arch/xtensa/include/asm/processor.h +++ b/arch/xtensa/include/asm/processor.h @@ -113,9 +113,9 @@ #define MAKE_RA_FOR_CALL(ra,ws) (((ra) & 0x3fffffff) | (ws) << 30) /* Convert return address to a valid pc - * Note: We assume that the stack pointer is in the same 1GB ranges as the ra + * Note: 'text' is the address within the same 1GB range as the ra */ -#define MAKE_PC_FROM_RA(ra,sp) (((ra) & 0x3fffffff) | ((sp) & 0xc0000000)) +#define MAKE_PC_FROM_RA(ra, text) (((ra) & 0x3fffffff) | ((unsigned long)(text) & 0xc0000000)) #elif defined(__XTENSA_CALL0_ABI__) @@ -125,9 +125,9 @@ #define MAKE_RA_FOR_CALL(ra, ws) (ra) /* Convert return address to a valid pc - * Note: We assume that the stack pointer is in the same 1GB ranges as the ra + * Note: 'text' is not used as 'ra' is always the full address */ -#define MAKE_PC_FROM_RA(ra, sp) (ra) +#define MAKE_PC_FROM_RA(ra, text) (ra) #else #error Unsupported Xtensa ABI diff --git a/arch/xtensa/include/asm/ptrace.h b/arch/xtensa/include/asm/ptrace.h index 308f209a4740..17c5cbd1832e 100644 --- a/arch/xtensa/include/asm/ptrace.h +++ b/arch/xtensa/include/asm/ptrace.h @@ -87,7 +87,7 @@ struct pt_regs { # define user_mode(regs) (((regs)->ps & 0x00000020)!=0) # define instruction_pointer(regs) ((regs)->pc) # define return_pointer(regs) (MAKE_PC_FROM_RA((regs)->areg[0], \ - (regs)->areg[1])) + (regs)->pc)) # ifndef CONFIG_SMP # define profile_pc(regs) instruction_pointer(regs) diff --git a/arch/xtensa/kernel/process.c b/arch/xtensa/kernel/process.c index 68e0e2f06d66..3138f72dcbe2 100644 --- a/arch/xtensa/kernel/process.c +++ b/arch/xtensa/kernel/process.c @@ -47,6 +47,7 @@ #include #include #include +#include #include extern void ret_from_fork(void); @@ -379,7 +380,7 @@ unsigned long __get_wchan(struct task_struct *p) int count = 0; sp = p->thread.sp; - pc = MAKE_PC_FROM_RA(p->thread.ra, p->thread.sp); + pc = MAKE_PC_FROM_RA(p->thread.ra, _text); do { if (sp < stack_page + sizeof(struct task_struct) || @@ -391,7 +392,7 @@ unsigned long __get_wchan(struct task_struct *p) /* Stack layout: sp-4: ra, sp-3: sp' */ - pc = MAKE_PC_FROM_RA(SPILL_SLOT(sp, 0), sp); + pc = MAKE_PC_FROM_RA(SPILL_SLOT(sp, 0), _text); sp = SPILL_SLOT(sp, 1); } while (count++ < 16); return 0; diff --git a/arch/xtensa/kernel/stacktrace.c b/arch/xtensa/kernel/stacktrace.c index dcba743305ef..b69044893287 100644 --- a/arch/xtensa/kernel/stacktrace.c +++ b/arch/xtensa/kernel/stacktrace.c @@ -13,6 +13,7 @@ #include #include +#include #include #include #include @@ -189,7 +190,7 @@ void walk_stackframe(unsigned long *sp, if (a1 <= (unsigned long)sp) break; - frame.pc = MAKE_PC_FROM_RA(a0, a1); + frame.pc = MAKE_PC_FROM_RA(a0, _text); frame.sp = a1; if (fn(&frame, data))