[PATCH] powerpc/64s: Reconnect tlb_flush() to hash__tlb_flush()

[PATCH] powerpc/64s: Reconnect tlb_flush() to hash__tlb_flush()

[Michael Ellerman]

Commit baf1ed24b27d ("powerpc/mm: Remove empty hash__ functions")
removed some empty hash MMU flushing routines, but got a bit overeager
and also removed the call to hash__tlb_flush() from tlb_flush().

In regular use this doesn't lead to any noticable breakage, which is a
little concerning. Presumably there are flushes happening via other
paths such as arch_leave_lazy_mmu_mode(), and/or a bit of luck.

Fix it by reinstating the call to hash__tlb_flush().

Fixes: baf1ed24b27d ("powerpc/mm: Remove empty hash__ functions")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/include/asm/book3s/64/tlbflush.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/powerpc/include/asm/book3s/64/tlbflush.h b/arch/powerpc/include/asm/book3s/64/tlbflush.h
index dd39313242b4..d5cd16270c5d 100644
--- a/arch/powerpc/include/asm/book3s/64/tlbflush.h
+++ b/arch/powerpc/include/asm/book3s/64/tlbflush.h
@@ -97,6 +97,8 @@ static inline void tlb_flush(struct mmu_gather *tlb)
 {
 	if (radix_enabled())
 		radix__tlb_flush(tlb);
+
+	return hash__tlb_flush(tlb);
 }
 
 #ifdef CONFIG_SMP
-- 
2.39.1

Re: [PATCH] powerpc/64s: Reconnect tlb_flush() to hash__tlb_flush()

[Michael Ellerman]

On Tue, 31 Jan 2023 22:14:07 +1100, Michael Ellerman wrote:
> Commit baf1ed24b27d ("powerpc/mm: Remove empty hash__ functions")
> removed some empty hash MMU flushing routines, but got a bit overeager
> and also removed the call to hash__tlb_flush() from tlb_flush().
> 
> In regular use this doesn't lead to any noticable breakage, which is a
> little concerning. Presumably there are flushes happening via other
> paths such as arch_leave_lazy_mmu_mode(), and/or a bit of luck.
> 
> [...]

Applied to powerpc/fixes.

[1/1] powerpc/64s: Reconnect tlb_flush() to hash__tlb_flush()
      https://git.kernel.org/powerpc/c/1665c027afb225882a5a0b014c45e84290b826c2

cheers