From: Suren Baghdasaryan <surenb@xxxxxxxxxx>
[ Upstream commit e870920bbe68e52335a4c31a059e6af6a9a59dbb ]
The change [1] missed ARM architecture when fixing major fault accounting
for page fault retry under per-VMA lock.
The user-visible effects is that it restores correct major fault
accounting that was broken after [2] was merged in 6.7 kernel. The
more detailed description is in [3] and this patch simply adds the
same fix to ARM architecture which I missed in [3].
Add missing code to fix ARM architecture fault accounting.
[1] 46e714c729c8 ("arch/mm/fault: fix major fault accounting when retrying under per-VMA lock")
[2] https://lore.kernel.org/all/20231006195318.4087158-6-willy@xxxxxxxxxxxxx/
[3] https://lore.kernel.org/all/20231226214610.109282-1-surenb@xxxxxxxxxx/
Link: https://lkml.kernel.org/r/20240123064305.2829244-1-surenb@xxxxxxxxxx
Fixes: 12214eba1992 ("mm: handle read faults under the VMA lock")
Reported-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx>
Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Cc: Alexander Gordeev <agordeev@xxxxxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Gerald Schaefer <gerald.schaefer@xxxxxxxxxxxxx>
Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Palmer Dabbelt <palmer@xxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/arm/mm/fault.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index e96fb40b9cc32..07565b593ed68 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -298,6 +298,8 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
goto done;
}
count_vm_vma_lock_event(VMA_LOCK_RETRY);
+ if (fault & VM_FAULT_MAJOR)
+ flags |= FAULT_FLAG_TRIED;
/* Quick path to respond to signals */
if (fault_signal_pending(fault, regs)) {
--
2.43.0
