6.6-stable review patch. If anyone has any objections, please let me know.
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From: Guenter Roeck linux@roeck-us.net
[ Upstream commit 882a2a724ee964c1ebe7268a91d5c8c8ddc796bf ]
Debugging shows a large number of unaligned access traps in the unwinder code. Code analysis reveals a number of issues with this code:
- handle_interruption is passed twice through dereference_kernel_function_descriptor() - ret_from_kernel_thread, syscall_exit, intr_return, _switch_to_ret, and _call_on_stack are passed through dereference_kernel_function_descriptor() even though they are not declared as function pointers.
To fix the problems, drop one of the calls to dereference_kernel_function_descriptor() for handle_interruption, and compare the other pointers directly.
Fixes: 6414b30b39f9 ("parisc: unwind: Avoid missing prototype warning for handle_interruption()") Fixes: 8e0ba125c2bf ("parisc/unwind: fix unwinder when CONFIG_64BIT is enabled") Cc: Helge Deller deller@gmx.de Cc: Sven Schnelle svens@stackframe.org Cc: John David Anglin dave.anglin@bell.net Cc: Charlie Jenkins charlie@rivosinc.com Cc: David Laight David.Laight@ACULAB.COM Signed-off-by: Guenter Roeck linux@roeck-us.net Signed-off-by: Helge Deller deller@gmx.de Signed-off-by: Sasha Levin sashal@kernel.org --- arch/parisc/kernel/unwind.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-)
diff --git a/arch/parisc/kernel/unwind.c b/arch/parisc/kernel/unwind.c index 27ae40a443b80..f7e0fee5ee55a 100644 --- a/arch/parisc/kernel/unwind.c +++ b/arch/parisc/kernel/unwind.c @@ -228,10 +228,8 @@ static int unwind_special(struct unwind_frame_info *info, unsigned long pc, int #ifdef CONFIG_IRQSTACKS extern void * const _call_on_stack; #endif /* CONFIG_IRQSTACKS */ - void *ptr;
- ptr = dereference_kernel_function_descriptor(&handle_interruption); - if (pc_is_kernel_fn(pc, ptr)) { + if (pc_is_kernel_fn(pc, handle_interruption)) { struct pt_regs *regs = (struct pt_regs *)(info->sp - frame_size - PT_SZ_ALGN); dbg("Unwinding through handle_interruption()\n"); info->prev_sp = regs->gr[30]; @@ -239,13 +237,13 @@ static int unwind_special(struct unwind_frame_info *info, unsigned long pc, int return 1; }
- if (pc_is_kernel_fn(pc, ret_from_kernel_thread) || - pc_is_kernel_fn(pc, syscall_exit)) { + if (pc == (unsigned long)&ret_from_kernel_thread || + pc == (unsigned long)&syscall_exit) { info->prev_sp = info->prev_ip = 0; return 1; }
- if (pc_is_kernel_fn(pc, intr_return)) { + if (pc == (unsigned long)&intr_return) { struct pt_regs *regs;
dbg("Found intr_return()\n"); @@ -257,14 +255,14 @@ static int unwind_special(struct unwind_frame_info *info, unsigned long pc, int }
if (pc_is_kernel_fn(pc, _switch_to) || - pc_is_kernel_fn(pc, _switch_to_ret)) { + pc == (unsigned long)&_switch_to_ret) { info->prev_sp = info->sp - CALLEE_SAVE_FRAME_SIZE; info->prev_ip = *(unsigned long *)(info->prev_sp - RP_OFFSET); return 1; }
#ifdef CONFIG_IRQSTACKS - if (pc_is_kernel_fn(pc, _call_on_stack)) { + if (pc == (unsigned long)&_call_on_stack) { info->prev_sp = *(unsigned long *)(info->sp - FRAME_SIZE - REG_SZ); info->prev_ip = *(unsigned long *)(info->sp - FRAME_SIZE - RP_OFFSET); return 1;