diff options
author | Hugh Dickins <hughd@google.com> | 2023-06-08 12:15:16 -0700 |
---|---|---|
committer | Andrew Morton <akpm@linux-foundation.org> | 2023-06-19 16:19:06 -0700 |
commit | e67b37c368b7cc24b8c0fe5ab6c44422312eab37 (patch) | |
tree | 8f795604f408baeec67d846712704b5b2d722de8 /arch/m68k/mm | |
parent | 0db639f768e6b6296bbc64689dd8823b7bdb765a (diff) |
m68k: allow pte_offset_map[_lock]() to fail
In rare transient cases, not yet made possible, pte_offset_map() and
pte_offset_map_lock() may not find a page table: handle appropriately.
Restructure cf_tlb_miss() with a pte_unmap() (previously omitted)
at label out, followed by one local_irq_restore() for all.
Link: https://lkml.kernel.org/r/795f6a7-bcca-cdf-ad2a-fbdaa232998c@google.com
Signed-off-by: Hugh Dickins <hughd@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/m68k/mm')
-rw-r--r-- | arch/m68k/mm/mcfmmu.c | 52 |
1 files changed, 21 insertions, 31 deletions
diff --git a/arch/m68k/mm/mcfmmu.c b/arch/m68k/mm/mcfmmu.c index 70aa0979e027..42f45abea37a 100644 --- a/arch/m68k/mm/mcfmmu.c +++ b/arch/m68k/mm/mcfmmu.c @@ -91,7 +91,8 @@ int cf_tlb_miss(struct pt_regs *regs, int write, int dtlb, int extension_word) p4d_t *p4d; pud_t *pud; pmd_t *pmd; - pte_t *pte; + pte_t *pte = NULL; + int ret = -1; int asid; local_irq_save(flags); @@ -100,47 +101,33 @@ int cf_tlb_miss(struct pt_regs *regs, int write, int dtlb, int extension_word) regs->pc + (extension_word * sizeof(long)); mm = (!user_mode(regs) && KMAPAREA(mmuar)) ? &init_mm : current->mm; - if (!mm) { - local_irq_restore(flags); - return -1; - } + if (!mm) + goto out; pgd = pgd_offset(mm, mmuar); - if (pgd_none(*pgd)) { - local_irq_restore(flags); - return -1; - } + if (pgd_none(*pgd)) + goto out; p4d = p4d_offset(pgd, mmuar); - if (p4d_none(*p4d)) { - local_irq_restore(flags); - return -1; - } + if (p4d_none(*p4d)) + goto out; pud = pud_offset(p4d, mmuar); - if (pud_none(*pud)) { - local_irq_restore(flags); - return -1; - } + if (pud_none(*pud)) + goto out; pmd = pmd_offset(pud, mmuar); - if (pmd_none(*pmd)) { - local_irq_restore(flags); - return -1; - } + if (pmd_none(*pmd)) + goto out; pte = (KMAPAREA(mmuar)) ? pte_offset_kernel(pmd, mmuar) : pte_offset_map(pmd, mmuar); - if (pte_none(*pte) || !pte_present(*pte)) { - local_irq_restore(flags); - return -1; - } + if (!pte || pte_none(*pte) || !pte_present(*pte)) + goto out; if (write) { - if (!pte_write(*pte)) { - local_irq_restore(flags); - return -1; - } + if (!pte_write(*pte)) + goto out; set_pte(pte, pte_mkdirty(*pte)); } @@ -161,9 +148,12 @@ int cf_tlb_miss(struct pt_regs *regs, int write, int dtlb, int extension_word) mmu_write(MMUOR, MMUOR_ACC | MMUOR_UAA); else mmu_write(MMUOR, MMUOR_ITLB | MMUOR_ACC | MMUOR_UAA); - + ret = 0; +out: + if (pte && !KMAPAREA(mmuar)) + pte_unmap(pte); local_irq_restore(flags); - return 0; + return ret; } void __init cf_bootmem_alloc(void) |