Le 23/04/2020 à 17:09, Naveen N. Rao a écrit :
With STRICT_KERNEL_RWX, we are currently ignoring return value from
__patch_instruction() in do_patch_instruction(), resulting in the error
not being propagated back. Fix the same.
Good patch.
Be aware that there is ongoing work which tend to wanting to replace
error reporting by BUG_ON() . See
https://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=166003
Fixes: 37bc3e5fd764f ("powerpc/lib/code-patching: Use alternate map for
patch_instruction()")
Signed-off-by: Naveen N. Rao <naveen.n....@linux.vnet.ibm.com>
---
arch/powerpc/lib/code-patching.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c
index 3345f039a876..5c713a6c0bd8 100644
--- a/arch/powerpc/lib/code-patching.c
+++ b/arch/powerpc/lib/code-patching.c
@@ -138,7 +138,7 @@ static inline int unmap_patch_area(unsigned long addr)
static int do_patch_instruction(unsigned int *addr, unsigned int instr)
{
- int err;
+ int err, rc = 0;
unsigned int *patch_addr = NULL;
unsigned long flags;
unsigned long text_poke_addr;
@@ -163,7 +163,7 @@ static int do_patch_instruction(unsigned int *addr,
unsigned int instr)
patch_addr = (unsigned int *)(text_poke_addr) +
((kaddr & ~PAGE_MASK) / sizeof(unsigned int));
- __patch_instruction(addr, instr, patch_addr);
+ rc = __patch_instruction(addr, instr, patch_addr);
err = unmap_patch_area(text_poke_addr);
if (err)
@@ -172,7 +172,7 @@ static int do_patch_instruction(unsigned int *addr,
unsigned int instr)
out:
local_irq_restore(flags);
- return err;
+ return rc ? rc : err;
That's not really consistent. __patch_instruction() and
unmap_patch_area() return a valid minus errno, while in case of
map_patch_area() failure, err has value -1
}
#else /* !CONFIG_STRICT_KERNEL_RWX */
Christophe
