powerpc: add a define for the user interrupt frame size

The user interrupt frame is a different size from the kernel frame, so
give it its own name.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221127124942.1665522-11-npiggin@gmail.com

diff --git a/arch/powerpc/include/asm/ptrace.h b/arch/powerpc/include/asm/ptrace.h
index fdd5064..705ce26 100644 (file)
--- a/arch/powerpc/include/asm/ptrace.h
+++ b/arch/powerpc/include/asm/ptrace.h
@@ -122,8 +122,7 @@ struct pt_regs
 
 #define STACK_FRAME_OVERHEAD   112     /* size of minimum stack frame */
 #define STACK_FRAME_LR_SAVE    2       /* Location of LR in stack frame */
-#define STACK_INT_FRAME_SIZE   (sizeof(struct pt_regs) + \
-                                STACK_FRAME_OVERHEAD + KERNEL_REDZONE_SIZE)
+#define STACK_USER_INT_FRAME_SIZE      (sizeof(struct pt_regs) + STACK_FRAME_OVERHEAD)
 #define STACK_INT_FRAME_REGS   STACK_FRAME_OVERHEAD
 #define STACK_INT_FRAME_MARKER (STACK_FRAME_OVERHEAD - 16)
 
@@ -143,7 +142,7 @@ struct pt_regs
 #define KERNEL_REDZONE_SIZE    0
 #define STACK_FRAME_OVERHEAD   16      /* size of minimum stack frame */
 #define STACK_FRAME_LR_SAVE    1       /* Location of LR in stack frame */
-#define STACK_INT_FRAME_SIZE   (sizeof(struct pt_regs) + STACK_FRAME_OVERHEAD)
+#define STACK_USER_INT_FRAME_SIZE      (sizeof(struct pt_regs) + STACK_FRAME_OVERHEAD)
 #define STACK_INT_FRAME_REGS   STACK_FRAME_OVERHEAD
 #define STACK_INT_FRAME_MARKER (STACK_FRAME_OVERHEAD - 8)
 #define STACK_FRAME_MIN_SIZE   STACK_FRAME_OVERHEAD
@@ -153,6 +152,7 @@ struct pt_regs
 
 #endif /* __powerpc64__ */
 
+#define STACK_INT_FRAME_SIZE   (KERNEL_REDZONE_SIZE + STACK_USER_INT_FRAME_SIZE)
 #define STACK_INT_FRAME_MARKER_LONGS   (STACK_INT_FRAME_MARKER/sizeof(long))
 
 #ifndef __ASSEMBLY__

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 6c0a3c6..010a5ee 100644 (file)
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1756,15 +1756,15 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
        klp_init_thread_info(p);
 
        /* Create initial stack frame. */
-       sp -= (sizeof(struct pt_regs) + STACK_FRAME_OVERHEAD);
+       sp -= STACK_USER_INT_FRAME_SIZE;
        ((unsigned long *)sp)[0] = 0;
 
        /* Copy registers */
-       childregs = (struct pt_regs *)(sp + STACK_FRAME_OVERHEAD);
+       childregs = (struct pt_regs *)(sp + STACK_INT_FRAME_REGS);
        if (unlikely(args->fn)) {
                /* kernel thread */
                memset(childregs, 0, sizeof(struct pt_regs));
-               childregs->gpr[1] = sp + (sizeof(struct pt_regs) + STACK_FRAME_OVERHEAD);
+               childregs->gpr[1] = sp + STACK_USER_INT_FRAME_SIZE;
                /* function */
                if (args->fn)
                        childregs->gpr[14] = ppc_function_entry((void *)args->fn);

diff --git a/arch/powerpc/kernel/stacktrace.c b/arch/powerpc/kernel/stacktrace.c
index 7efa0ec..453ac31 100644 (file)
--- a/arch/powerpc/kernel/stacktrace.c
+++ b/arch/powerpc/kernel/stacktrace.c
@@ -77,7 +77,7 @@ int __no_sanitize_address arch_stack_walk_reliable(stack_trace_consume_fn consum
                /*
                 * For user tasks, this is the SP value loaded on
                 * kernel entry, see "PACAKSAVE(r13)" in _switch() and
-                * system_call_common()/EXCEPTION_PROLOG_COMMON().
+                * system_call_common().
                 *
                 * Likewise for non-swapper kernel threads,
                 * this also happens to be the top of the stack
@@ -88,7 +88,7 @@ int __no_sanitize_address arch_stack_walk_reliable(stack_trace_consume_fn consum
                 * an unreliable stack trace until it's been
                 * _switch()'ed to for the first time.
                 */
-               stack_end -= STACK_FRAME_OVERHEAD + sizeof(struct pt_regs);
+               stack_end -= STACK_USER_INT_FRAME_SIZE;
        } else {
                /*
                 * idle tasks have a custom stack layout,