summaryrefslogtreecommitdiff
path: root/arch/powerpc
diff options
context:
space:
mode:
authorMichael Ellerman <mpe@ellerman.id.au>2018-10-12 15:13:17 +0300
committerMichael Ellerman <mpe@ellerman.id.au>2018-10-14 10:04:09 +0300
commit002af9391bfbe84f8e491bb10bd9c6001a6becee (patch)
treef7e1cdb3d2e2f48327908e4211b3074bca8c6659 /arch/powerpc
parent7f995d3ba6f2bfbe274f5a012f5b549f881e78fe (diff)
downloadlinux-002af9391bfbe84f8e491bb10bd9c6001a6becee.tar.xz
powerpc: Split user/kernel definitions of struct pt_regs
We use a shared definition for struct pt_regs in uapi/asm/ptrace.h. That means the layout of the structure is ABI, ie. we can't change it. That would be fine if it was only used to describe the user-visible register state of a process, but it's also the struct we use in the kernel to describe the registers saved in an interrupt frame. We'd like more flexibility in the content (and possibly layout) of the kernel version of the struct, but currently that's not possible. So split the definition into a user-visible definition which remains unchanged, and a kernel internal one. At the moment they're still identical, and we check that at build time. That's because we have code (in ptrace etc.) that assumes that they are the same. We will fix that code in future patches, and then we can break the strict symmetry between the two structs. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc')
-rw-r--r--arch/powerpc/include/asm/ptrace.h27
-rw-r--r--arch/powerpc/include/uapi/asm/ptrace.h7
-rw-r--r--arch/powerpc/kernel/ptrace.c39
3 files changed, 72 insertions, 1 deletions
diff --git a/arch/powerpc/include/asm/ptrace.h b/arch/powerpc/include/asm/ptrace.h
index 447cbd1bee99..3dd15024db93 100644
--- a/arch/powerpc/include/asm/ptrace.h
+++ b/arch/powerpc/include/asm/ptrace.h
@@ -26,6 +26,33 @@
#include <uapi/asm/ptrace.h>
#include <asm/asm-const.h>
+#ifndef __ASSEMBLY__
+struct pt_regs
+{
+ union {
+ struct user_pt_regs user_regs;
+ struct {
+ unsigned long gpr[32];
+ unsigned long nip;
+ unsigned long msr;
+ unsigned long orig_gpr3;
+ unsigned long ctr;
+ unsigned long link;
+ unsigned long xer;
+ unsigned long ccr;
+#ifdef CONFIG_PPC64
+ unsigned long softe;
+#else
+ unsigned long mq;
+#endif
+ unsigned long trap;
+ unsigned long dar;
+ unsigned long dsisr;
+ unsigned long result;
+ };
+ };
+};
+#endif
#ifdef __powerpc64__
diff --git a/arch/powerpc/include/uapi/asm/ptrace.h b/arch/powerpc/include/uapi/asm/ptrace.h
index 55c7a131d2ab..f5f1ccc740fc 100644
--- a/arch/powerpc/include/uapi/asm/ptrace.h
+++ b/arch/powerpc/include/uapi/asm/ptrace.h
@@ -29,7 +29,12 @@
#ifndef __ASSEMBLY__
-struct pt_regs {
+#ifdef __KERNEL__
+struct user_pt_regs
+#else
+struct pt_regs
+#endif
+{
unsigned long gpr[32];
unsigned long nip;
unsigned long msr;
diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c
index 4e372f54088f..939d7f81bbbe 100644
--- a/arch/powerpc/kernel/ptrace.c
+++ b/arch/powerpc/kernel/ptrace.c
@@ -3335,3 +3335,42 @@ void do_syscall_trace_leave(struct pt_regs *regs)
user_enter();
}
+
+void __init pt_regs_check(void)
+{
+ BUILD_BUG_ON(offsetof(struct pt_regs, gpr) !=
+ offsetof(struct user_pt_regs, gpr));
+ BUILD_BUG_ON(offsetof(struct pt_regs, nip) !=
+ offsetof(struct user_pt_regs, nip));
+ BUILD_BUG_ON(offsetof(struct pt_regs, msr) !=
+ offsetof(struct user_pt_regs, msr));
+ BUILD_BUG_ON(offsetof(struct pt_regs, msr) !=
+ offsetof(struct user_pt_regs, msr));
+ BUILD_BUG_ON(offsetof(struct pt_regs, orig_gpr3) !=
+ offsetof(struct user_pt_regs, orig_gpr3));
+ BUILD_BUG_ON(offsetof(struct pt_regs, ctr) !=
+ offsetof(struct user_pt_regs, ctr));
+ BUILD_BUG_ON(offsetof(struct pt_regs, link) !=
+ offsetof(struct user_pt_regs, link));
+ BUILD_BUG_ON(offsetof(struct pt_regs, xer) !=
+ offsetof(struct user_pt_regs, xer));
+ BUILD_BUG_ON(offsetof(struct pt_regs, ccr) !=
+ offsetof(struct user_pt_regs, ccr));
+#ifdef __powerpc64__
+ BUILD_BUG_ON(offsetof(struct pt_regs, softe) !=
+ offsetof(struct user_pt_regs, softe));
+#else
+ BUILD_BUG_ON(offsetof(struct pt_regs, mq) !=
+ offsetof(struct user_pt_regs, mq));
+#endif
+ BUILD_BUG_ON(offsetof(struct pt_regs, trap) !=
+ offsetof(struct user_pt_regs, trap));
+ BUILD_BUG_ON(offsetof(struct pt_regs, dar) !=
+ offsetof(struct user_pt_regs, dar));
+ BUILD_BUG_ON(offsetof(struct pt_regs, dsisr) !=
+ offsetof(struct user_pt_regs, dsisr));
+ BUILD_BUG_ON(offsetof(struct pt_regs, result) !=
+ offsetof(struct user_pt_regs, result));
+
+ BUILD_BUG_ON(sizeof(struct user_pt_regs) > sizeof(struct pt_regs));
+}