[PATCH] powerpc/kexec: blacklist functions called in real mode for kprobe

[Hari Bathini]

As kprobe does not handle events happening in real mode, blacklist the
functions that only get called in real mode or in kexec sequence with
MMU turned off.

Signed-off-by: Hari Bathini <hbathini at linux.ibm.com>
---
 arch/powerpc/kernel/head_64.S            |    2 ++
 arch/powerpc/kexec/core_64.c             |    6 ++++--
 arch/powerpc/mm/book3s64/hash_native.c   |    2 +-
 arch/powerpc/mm/book3s64/pgtable.c       |    4 ++--
 arch/powerpc/mm/book3s64/radix_pgtable.c |    3 ++-
 arch/powerpc/platforms/ps3/htab.c        |    3 ++-
 arch/powerpc/platforms/ps3/mm.c          |    8 ++++++--
 arch/powerpc/platforms/pseries/lpar.c    |    9 ++++++---
 8 files changed, 25 insertions(+), 12 deletions(-)

diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
index 79930b0bc781..f17ae2083733 100644
--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S
@@ -712,6 +712,8 @@ _GLOBAL(copy_and_flush)
 	isync
 	blr
 
+_ASM_NOKPROBE_SYMBOL(copy_and_flush); /* Called in real mode */
+
 .align 8
 copy_to_here:
 
diff --git a/arch/powerpc/kexec/core_64.c b/arch/powerpc/kexec/core_64.c
index 8a449b2d8715..84618d3c8013 100644
--- a/arch/powerpc/kexec/core_64.c
+++ b/arch/powerpc/kexec/core_64.c
@@ -72,7 +72,8 @@ int default_machine_kexec_prepare(struct kimage *image)
 	return 0;
 }
 
-static void copy_segments(unsigned long ind)
+/* Called during kexec sequence with MMU off */
+static notrace void copy_segments(unsigned long ind)
 {
 	unsigned long entry;
 	unsigned long *ptr;
@@ -105,7 +106,8 @@ static void copy_segments(unsigned long ind)
 	}
 }
 
-void kexec_copy_flush(struct kimage *image)
+/* Called during kexec sequence with MMU off */
+notrace void kexec_copy_flush(struct kimage *image)
 {
 	long i, nr_segments = image->nr_segments;
 	struct  kexec_segment ranges[KEXEC_SEGMENT_MAX];
diff --git a/arch/powerpc/mm/book3s64/hash_native.c b/arch/powerpc/mm/book3s64/hash_native.c
index 52e170bd95ae..d8279bfe68ea 100644
--- a/arch/powerpc/mm/book3s64/hash_native.c
+++ b/arch/powerpc/mm/book3s64/hash_native.c
@@ -787,7 +787,7 @@ static void hpte_decode(struct hash_pte *hpte, unsigned long slot,
  * TODO: add batching support when enabled.  remember, no dynamic memory here,
  * although there is the control page available...
  */
-static void native_hpte_clear(void)
+static notrace void native_hpte_clear(void)
 {
 	unsigned long vpn = 0;
 	unsigned long slot, slots;
diff --git a/arch/powerpc/mm/book3s64/pgtable.c b/arch/powerpc/mm/book3s64/pgtable.c
index 9ffa65074cb0..300099de553b 100644
--- a/arch/powerpc/mm/book3s64/pgtable.c
+++ b/arch/powerpc/mm/book3s64/pgtable.c
@@ -172,8 +172,8 @@ pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
 }
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 
-/* For use by kexec */
-void mmu_cleanup_all(void)
+/* For use by kexec, called with MMU off */
+notrace void mmu_cleanup_all(void)
 {
 	if (radix_enabled())
 		radix__mmu_cleanup_all();
diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
index e50ddf129c15..ae20add7954a 100644
--- a/arch/powerpc/mm/book3s64/radix_pgtable.c
+++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -679,7 +679,8 @@ void radix__early_init_mmu_secondary(void)
 	mtspr(SPRN_UAMOR, 0);
 }
 
-void radix__mmu_cleanup_all(void)
+/* Called during kexec sequence with MMU off */
+notrace void radix__mmu_cleanup_all(void)
 {
 	unsigned long lpcr;
 
diff --git a/arch/powerpc/platforms/ps3/htab.c b/arch/powerpc/platforms/ps3/htab.c
index 7ddc7ec6a7c0..ef710a715903 100644
--- a/arch/powerpc/platforms/ps3/htab.c
+++ b/arch/powerpc/platforms/ps3/htab.c
@@ -169,7 +169,8 @@ static void ps3_hpte_invalidate(unsigned long slot, unsigned long vpn,
 	spin_unlock_irqrestore(&ps3_htab_lock, flags);
 }
 
-static void ps3_hpte_clear(void)
+/* Called during kexec sequence with MMU off */
+static notrace void ps3_hpte_clear(void)
 {
 	unsigned long hpte_count = (1UL << ppc64_pft_size) >> 4;
 	u64 i;
diff --git a/arch/powerpc/platforms/ps3/mm.c b/arch/powerpc/platforms/ps3/mm.c
index a81eac35d900..9c44f335c0b9 100644
--- a/arch/powerpc/platforms/ps3/mm.c
+++ b/arch/powerpc/platforms/ps3/mm.c
@@ -195,9 +195,11 @@ void __init ps3_mm_vas_create(unsigned long* htab_size)
 
 /**
  * ps3_mm_vas_destroy -
+ *
+ * called during kexec sequence with MMU off.
  */
 
-void ps3_mm_vas_destroy(void)
+notrace void ps3_mm_vas_destroy(void)
 {
 	int result;
 
@@ -1243,9 +1245,11 @@ void __init ps3_mm_init(void)
 
 /**
  * ps3_mm_shutdown - final cleanup of address space
+ *
+ * called during kexec sequence with MMU off.
  */
 
-void ps3_mm_shutdown(void)
+notrace void ps3_mm_shutdown(void)
 {
 	ps3_mm_region_destroy(&map.r1);
 }
diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c
index dab356e3ff87..869ef638698a 100644
--- a/arch/powerpc/platforms/pseries/lpar.c
+++ b/arch/powerpc/platforms/pseries/lpar.c
@@ -801,7 +801,8 @@ static long pSeries_lpar_hpte_remove(unsigned long hpte_group)
 	return -1;
 }
 
-static void manual_hpte_clear_all(void)
+/* Called during kexec sequence with MMU off */
+static notrace void manual_hpte_clear_all(void)
 {
 	unsigned long size_bytes = 1UL << ppc64_pft_size;
 	unsigned long hpte_count = size_bytes >> 4;
@@ -834,7 +835,8 @@ static void manual_hpte_clear_all(void)
 	}
 }
 
-static int hcall_hpte_clear_all(void)
+/* Called during kexec sequence with MMU off */
+static notrace int hcall_hpte_clear_all(void)
 {
 	int rc;
 
@@ -845,7 +847,8 @@ static int hcall_hpte_clear_all(void)
 	return rc;
 }
 
-static void pseries_hpte_clear_all(void)
+/* Called during kexec sequence with MMU off */
+static notrace void pseries_hpte_clear_all(void)
 {
 	int rc;