Capture the protection key that got violated in paca.
This value will be later used to inform the signal
handler.
Signed-off-by: Ram Pai <linux...@us.ibm.com>
---
arch/powerpc/include/asm/paca.h | 3 +++
arch/powerpc/kernel/asm-offsets.c | 5 +++++
arch/powerpc/mm/fault.c | 11 ++++++++++-
3 files changed, 18 insertions(+), 1 deletions(-)
diff --git a/arch/powerpc/include/asm/paca.h b/arch/powerpc/include/asm/paca.h
index 04b60af..51c89c1 100644
--- a/arch/powerpc/include/asm/paca.h
+++ b/arch/powerpc/include/asm/paca.h
@@ -97,6 +97,9 @@ struct paca_struct {
struct dtl_entry *dispatch_log_end;
#endif /* CONFIG_PPC_STD_MMU_64 */
u64 dscr_default; /* per-CPU default DSCR */
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ u16 paca_pkey; /* exception causing pkey */
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
#ifdef CONFIG_PPC_STD_MMU_64
/*
diff --git a/arch/powerpc/kernel/asm-offsets.c
b/arch/powerpc/kernel/asm-offsets.c
index 8cfb20e..361f0d4 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -241,6 +241,11 @@ int main(void)
OFFSET(PACAHWCPUID, paca_struct, hw_cpu_id);
OFFSET(PACAKEXECSTATE, paca_struct, kexec_state);
OFFSET(PACA_DSCR_DEFAULT, paca_struct, dscr_default);
+
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ OFFSET(PACA_PKEY, paca_struct, paca_pkey);
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
OFFSET(ACCOUNT_STARTTIME, paca_struct, accounting.starttime);
OFFSET(ACCOUNT_STARTTIME_USER, paca_struct, accounting.starttime_user);
OFFSET(ACCOUNT_USER_TIME, paca_struct, accounting.utime);
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index a16bc43..ad31f6e 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -153,6 +153,7 @@ static int bad_page_fault_exception(struct pt_regs *regs,
unsigned long address,
#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
if (si_code & DSISR_KEYFAULT) {
+ get_paca()->paca_pkey = get_pte_pkey(current->mm, address);
sig = SIGSEGV;
code = SEGV_PKUERR;
}
@@ -509,8 +510,16 @@ static int __do_page_fault(struct pt_regs *regs, unsigned
long address,
#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
if (!arch_vma_access_permitted(vma, flags & FAULT_FLAG_WRITE,
- is_exec, 0))
+ is_exec, 0)) {
+ /*
+ * The pgd-pdt...pmd-pte tree may not have been fully setup.
+ * Hence we cannot walk the tree to locate the pte, to locate
+ * the key. Hence lets use vma_pkey() to get the key; instead
+ * of get_pte_pkey().
+ */
+ get_paca()->paca_pkey = vma_pkey(vma);
return __bad_area(regs, address, SEGV_PKUERR);
+ }
#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
--
1.7.1
