summaryrefslogtreecommitdiffstats
path: root/arch
diff options
context:
space:
mode:
authorChristophe Leroy <christophe.leroy@c-s.fr>2017-11-21 15:28:20 +0100
committerMichael Ellerman <mpe@ellerman.id.au>2017-11-22 23:04:20 +1100
commit252eb55816a6f69ef9464cad303cdb3326cdc61d (patch)
tree82da0aef8fcf25b6696049d5cae17d175ff9c800 /arch
parentf3f1dfd600ff82b18b7ea73d80eb27f476a6aa97 (diff)
downloadlinux-252eb55816a6f69ef9464cad303cdb3326cdc61d.tar.bz2
powerpc: Fix boot on BOOK3S_32 with CONFIG_STRICT_KERNEL_RWX
On powerpc32, patch_instruction() is called by apply_feature_fixups() which is called from early_init() There is the following note in front of early_init(): * Note that the kernel may be running at an address which is different * from the address that it was linked at, so we must use RELOC/PTRRELOC * to access static data (including strings). -- paulus Therefore, slab_is_available() cannot be called yet, and text_poke_area must be addressed with PTRRELOC() Fixes: 95902e6c8864 ("powerpc/mm: Implement STRICT_KERNEL_RWX on PPC32") Cc: stable@vger.kernel.org # v4.14+ Reported-by: Meelis Roos <mroos@linux.ee> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch')
-rw-r--r--arch/powerpc/lib/code-patching.c6
1 files changed, 2 insertions, 4 deletions
diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c
index c9de03e0c1f1..d469224c4ada 100644
--- a/arch/powerpc/lib/code-patching.c
+++ b/arch/powerpc/lib/code-patching.c
@@ -21,6 +21,7 @@
#include <asm/tlbflush.h>
#include <asm/page.h>
#include <asm/code-patching.h>
+#include <asm/setup.h>
static int __patch_instruction(unsigned int *addr, unsigned int instr)
{
@@ -146,11 +147,8 @@ int patch_instruction(unsigned int *addr, unsigned int instr)
* During early early boot patch_instruction is called
* when text_poke_area is not ready, but we still need
* to allow patching. We just do the plain old patching
- * We use slab_is_available and per cpu read * via this_cpu_read
- * of text_poke_area. Per-CPU areas might not be up early
- * this can create problems with just using this_cpu_read()
*/
- if (!slab_is_available() || !this_cpu_read(text_poke_area))
+ if (!this_cpu_read(*PTRRELOC(&text_poke_area)))
return __patch_instruction(addr, instr);
local_irq_save(flags);