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Subject[PATCH v2] powerpc/4xx: Fix setup_kuep() on SMP
Date
On SMP, setup_kuep() is also called from start_secondary() since
commit 86f46f343272 ("powerpc/32s: Initialise KUAP and KUEP in C").

start_secondary() is not an __init function.

Remove the __init marker from setup_kuep() and bail out when
not caller on the first CPU as the work is already done.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: 10248dcba120 ("powerpc/44x: Implement Kernel Userspace Exec Protection (KUEP)")
Fixes: 86f46f343272 ("powerpc/32s: Initialise KUAP and KUEP in C").
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
v2: Add missing asm/smp.h to avoid build failure without CONFIG_SMP
---
arch/powerpc/mm/nohash/44x.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/mm/nohash/44x.c b/arch/powerpc/mm/nohash/44x.c
index 7da6d1e9fc9b..e079f26b267e 100644
--- a/arch/powerpc/mm/nohash/44x.c
+++ b/arch/powerpc/mm/nohash/44x.c
@@ -25,6 +25,7 @@
#include <asm/page.h>
#include <asm/cacheflush.h>
#include <asm/code-patching.h>
+#include <asm/smp.h>

#include <mm/mmu_decl.h>

@@ -241,8 +242,11 @@ void __init mmu_init_secondary(int cpu)
#endif /* CONFIG_SMP */

#ifdef CONFIG_PPC_KUEP
-void __init setup_kuep(bool disabled)
+void setup_kuep(bool disabled)
{
+ if (smp_processor_id() != boot_cpuid)
+ return;
+
if (disabled)
patch_instruction_site(&patch__tlb_44x_kuep, ppc_inst(PPC_RAW_NOP()));
else
--
2.25.0
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