diff options
| author | Hugh Dickins <hughd@google.com> | 2023-06-15 16:02:43 -0700 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-06-19 16:19:07 -0700 |
| commit | 17b25a3801d11c28374a37cc672823cedb0f10d3 (patch) | |
| tree | 55bad5fb751a12f8e04203cc15eee6a9a6702baa /arch | |
| parent | 505a23a5f8934175d2b66fb5ea03a8c519a28e44 (diff) | |
| download | lwn-17b25a3801d11c28374a37cc672823cedb0f10d3.tar.gz lwn-17b25a3801d11c28374a37cc672823cedb0f10d3.zip | |
mips: add pte_unmap() to balance pte_offset_map()
To keep balance in future, __update_tlb() remember to pte_unmap() after
pte_offset_map(). This is an odd case, since the caller has already done
pte_offset_map_lock(), then mips forgets the address and recalculates it;
but my two naive attempts to clean that up did more harm than good.
Link: https://lkml.kernel.org/r/addfcb3-b5f4-976e-e050-a2508e589cfe@google.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Yu Zhao <yuzhao@google.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Alexandre Ghiti <alexghiti@rivosinc.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: John David Anglin <dave.anglin@bell.net>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/mips/mm/tlb-r4k.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/arch/mips/mm/tlb-r4k.c b/arch/mips/mm/tlb-r4k.c index 1b939abbe4ca..93c2d695588a 100644 --- a/arch/mips/mm/tlb-r4k.c +++ b/arch/mips/mm/tlb-r4k.c @@ -297,7 +297,7 @@ void __update_tlb(struct vm_area_struct * vma, unsigned long address, pte_t pte) p4d_t *p4dp; pud_t *pudp; pmd_t *pmdp; - pte_t *ptep; + pte_t *ptep, *ptemap = NULL; int idx, pid; /* @@ -344,7 +344,12 @@ void __update_tlb(struct vm_area_struct * vma, unsigned long address, pte_t pte) } else #endif { - ptep = pte_offset_map(pmdp, address); + ptemap = ptep = pte_offset_map(pmdp, address); + /* + * update_mmu_cache() is called between pte_offset_map_lock() + * and pte_unmap_unlock(), so we can assume that ptep is not + * NULL here: and what should be done below if it were NULL? + */ #if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32) #ifdef CONFIG_XPA @@ -373,6 +378,9 @@ void __update_tlb(struct vm_area_struct * vma, unsigned long address, pte_t pte) tlbw_use_hazard(); htw_start(); flush_micro_tlb_vm(vma); + + if (ptemap) + pte_unmap(ptemap); local_irq_restore(flags); } |