Le 14/12/2022 à 12:48, Christophe Leroy a écrit :
Le 14/12/2022 à 12:39, Nicholas Piggin a écrit :
On Wed Dec 14, 2022 at 6:39 PM AEST, Christophe Leroy wrote:
Le 14/12/2022 à 05:42, Nicholas Miehlbradt a écrit :
Walks the stack when copy_{to,from}_user address is in the stack to
ensure that the object being copied is entirely within a single stack
frame.
Substatially similar to the x86 implementation except using the back
chain to traverse the stack and identify stack frame boundaries.
Signed-off-by: Nicholas Miehlbradt <nicho...@linux.ibm.com>
---
arch/powerpc/Kconfig | 1 +
arch/powerpc/include/asm/thread_info.h | 38
++++++++++++++++++++++++++
2 files changed, 39 insertions(+)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 2ca5418457ed..4c59d139ea83 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -198,6 +198,7 @@ config PPC
select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN
select HAVE_ARCH_KFENCE if
ARCH_SUPPORTS_DEBUG_PAGEALLOC
select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
+ select HAVE_ARCH_WITHIN_STACK_FRAMES if PPC64
Why don't you do something that works for both PPC32 and PPC64 ?
+1
select HAVE_ARCH_KGDB
select HAVE_ARCH_MMAP_RND_BITS
select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
diff --git a/arch/powerpc/include/asm/thread_info.h
b/arch/powerpc/include/asm/thread_info.h
index af58f1ed3952..efdf39e07884 100644
--- a/arch/powerpc/include/asm/thread_info.h
+++ b/arch/powerpc/include/asm/thread_info.h
@@ -186,6 +186,44 @@ static inline bool
test_thread_local_flags(unsigned int flags)
#define is_elf2_task() (0)
#endif
+#ifdef CONFIG_PPC64
+
+#ifdef CONFIG_PPC64_ELF_ABI_V1
+#define PARAMETER_SAVE_OFFSET 48
+#else
+#define PARAMETER_SAVE_OFFSET 32
+#endif
Why not use STACK_INT_FRAME_REGS, defined in asm/ptrace.h ?
I think use a STACK_FRAME prefixed define in asm/ptrace.h, but maybe
avoid overloading the STACK_INT_ stuff for this.
Maybe I should have written _already_ defined :
$ git grep -n STACK_INT_FRAME_REGS arch/powerpc/include/asm/
arch/powerpc/include/asm/ptrace.h:126:#define STACK_INT_FRAME_REGS
(STACK_FRAME_MIN_SIZE + 16)
arch/powerpc/include/asm/ptrace.h:138:#define STACK_INT_FRAME_REGS
STACK_FRAME_MIN_SIZE
arch/powerpc/include/asm/ptrace.h:155:#define STACK_INT_FRAME_REGS
STACK_FRAME_MIN_SIZE
Looks like I misread STACK_FRAME_MIN_SIZE.
So yes, we need a new macro for it.
What about STACK_FRAME_PARAMS ?
