The WARN() in do_page_fault() is useless the problem is not in
do_page_fault() but on the place which generated the DSI exception.
We already have a dump from the Oops, no need of a WARN() in addition
The warning emitted by bad_kernel_fault() is good enough.
Signed-off-by: Christophe Leroy <christophe.le...@csgroup.eu>
---
v2: New (Partly taken from patch "powerpc/mm: Kill the task on KUAP fault")
---
arch/powerpc/include/asm/book3s/32/kup.h | 6 +-----
arch/powerpc/include/asm/book3s/64/kup-radix.h | 7 ++++---
arch/powerpc/include/asm/nohash/32/kup-8xx.h | 3 +--
3 files changed, 6 insertions(+), 10 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/32/kup.h
b/arch/powerpc/include/asm/book3s/32/kup.h
index 32fd4452e960..a0117a9d5b06 100644
--- a/arch/powerpc/include/asm/book3s/32/kup.h
+++ b/arch/powerpc/include/asm/book3s/32/kup.h
@@ -183,11 +183,7 @@ bad_kuap_fault(struct pt_regs *regs, unsigned long
address, bool is_write)
unsigned long begin = regs->kuap & 0xf0000000;
unsigned long end = regs->kuap << 28;
- if (!is_write)
- return false;
-
- return WARN(address < begin || address >= end,
- "Bug: write fault blocked by segment registers !");
+ return is_write && (address < begin || address >= end);
}
#endif /* CONFIG_PPC_KUAP */
diff --git a/arch/powerpc/include/asm/book3s/64/kup-radix.h
b/arch/powerpc/include/asm/book3s/64/kup-radix.h
index 3ee1ec60be84..8bdf559a4b32 100644
--- a/arch/powerpc/include/asm/book3s/64/kup-radix.h
+++ b/arch/powerpc/include/asm/book3s/64/kup-radix.h
@@ -161,9 +161,10 @@ static inline void restore_user_access(unsigned long flags)
static inline bool
bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
{
- return WARN(mmu_has_feature(MMU_FTR_RADIX_KUAP) &&
- (regs->kuap & (is_write ? AMR_KUAP_BLOCK_WRITE :
AMR_KUAP_BLOCK_READ)),
- "Bug: %s fault blocked by AMR!", is_write ? "Write" :
"Read");
+ if (!mmu_has_feature(MMU_FTR_RADIX_KUAP))
+ return false;
+
+ return !!(regs->kuap & (is_write ? AMR_KUAP_BLOCK_WRITE :
AMR_KUAP_BLOCK_READ));
}
#else /* CONFIG_PPC_KUAP */
static inline void kuap_restore_amr(struct pt_regs *regs, unsigned long amr)
diff --git a/arch/powerpc/include/asm/nohash/32/kup-8xx.h
b/arch/powerpc/include/asm/nohash/32/kup-8xx.h
index 567cdc557402..17a4a616436f 100644
--- a/arch/powerpc/include/asm/nohash/32/kup-8xx.h
+++ b/arch/powerpc/include/asm/nohash/32/kup-8xx.h
@@ -63,8 +63,7 @@ static inline void restore_user_access(unsigned long flags)
static inline bool
bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
{
- return WARN(!((regs->kuap ^ MD_APG_KUAP) & 0xff000000),
- "Bug: fault blocked by AP register !");
+ return !((regs->kuap ^ MD_APG_KUAP) & 0xff000000);
}
#endif /* !__ASSEMBLY__ */
--
2.25.0
