From: Hugh Dickins <hughd@google•com>
To: Andrew Morton <akpm@linux-foundation•org>
Cc: linux-ia64@vger•kernel.org, David Hildenbrand <david@redhat•com>,
Peter Zijlstra <peterz@infradead•org>,
Catalin Marinas <catalin.marinas@arm•com>,
Qi Zheng <zhengqi.arch@bytedance•com>,
linux-kernel@vger•kernel.org, Max Filippov <jcmvbkbc@gmail•com>,
sparclinux@vger•kernel.org,
Alexander Gordeev <agordeev@linux•ibm.com>,
Claudio Imbrenda <imbrenda@linux•ibm.com>,
Will Deacon <will@kernel•org>, Greg Ungerer <gerg@linux-m68k•org>,
linux-s390@vger•kernel.org, linux-sh@vger•kernel.org,
Helge Deller <deller@gmx•de>,
x86@kernel•org, Russell King <linux@armlinux•org.uk>,
Matthew Wilcox <willy@infradead•org>,
Geert Uytterhoeven <geert@linux-m68k•org>,
Christian Borntraeger <borntraeger@linux•ibm.com>,
Alexandre Ghiti <alexghiti@rivosinc•com>,
Heiko Carstens <hca@linux•ibm.com>,
linux-m68k@lists•linux-m68k.org,
John Paul Adrian Glaubitz <glaubitz@physik•fu-berlin.de>,
John David Anglin <dave.anglin@bell•net>,
Suren Baghdasaryan <surenb@google•com>,
linux-arm-kernel@lists•infradead.org,
C hris Zankel <chris@zankel•net>, Michal Simek <monstr@monstr•eu>,
Thomas Bogendoerfer <tsbogend@alpha•franken.de>,
linux-parisc@vger•kernel.org, linux-mm@kvack•org,
linux-mips@vger•kernel.org, linux-riscv@lists•infradead.org,
Palmer Dabbelt <palmer@dabbelt•com>,
"Kirill A. Shutemov" <kirill.shutemov@linux•intel.com>,
"Aneesh Kumar K.V" <aneesh.kumar@linux•ibm.com>,
linuxppc-dev@lists•ozlabs.org,
"David S. Miller" <davem@davemloft•net>,
Mike Rapoport <rppt@kernel•org>,
Mike Kravetz <mike.kravetz@oracle•com>
Subject: [PATCH v2 05/23] m68k: allow pte_offset_map[_lock]() to fail
Date: Thu, 8 Jun 2023 12:15:16 -0700 (PDT) [thread overview]
Message-ID: <795f6a7-bcca-cdf-ad2a-fbdaa232998c@google.com> (raw)
In-Reply-To: <a4963be9-7aa6-350-66d0-2ba843e1af44@google.com>
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.
Signed-off-by: Hugh Dickins <hughd@google•com>
---
arch/m68k/include/asm/mmu_context.h | 6 ++--
arch/m68k/kernel/sys_m68k.c | 2 ++
arch/m68k/mm/mcfmmu.c | 52 ++++++++++++-----------------
3 files changed, 27 insertions(+), 33 deletions(-)
diff --git a/arch/m68k/include/asm/mmu_context.h b/arch/m68k/include/asm/mmu_context.h
index 8ed6ac14d99f..141bbdfad960 100644
--- a/arch/m68k/include/asm/mmu_context.h
+++ b/arch/m68k/include/asm/mmu_context.h
@@ -99,7 +99,7 @@ static inline void load_ksp_mmu(struct task_struct *task)
p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
- pte_t *pte;
+ pte_t *pte = NULL;
unsigned long mmuar;
local_irq_save(flags);
@@ -139,7 +139,7 @@ static inline void load_ksp_mmu(struct task_struct *task)
pte = (mmuar >= PAGE_OFFSET) ? pte_offset_kernel(pmd, mmuar)
: pte_offset_map(pmd, mmuar);
- if (pte_none(*pte) || !pte_present(*pte))
+ if (!pte || pte_none(*pte) || !pte_present(*pte))
goto bug;
set_pte(pte, pte_mkyoung(*pte));
@@ -161,6 +161,8 @@ static inline void load_ksp_mmu(struct task_struct *task)
bug:
pr_info("ksp load failed: mm=0x%p ksp=0x08%lx\n", mm, mmuar);
end:
+ if (pte && mmuar < PAGE_OFFSET)
+ pte_unmap(pte);
local_irq_restore(flags);
}
diff --git a/arch/m68k/kernel/sys_m68k.c b/arch/m68k/kernel/sys_m68k.c
index bd0274c7592e..c586034d2a7a 100644
--- a/arch/m68k/kernel/sys_m68k.c
+++ b/arch/m68k/kernel/sys_m68k.c
@@ -488,6 +488,8 @@ sys_atomic_cmpxchg_32(unsigned long newval, int oldval, int d3, int d4, int d5,
if (!pmd_present(*pmd))
goto bad_access;
pte = pte_offset_map_lock(mm, pmd, (unsigned long)mem, &ptl);
+ if (!pte)
+ goto bad_access;
if (!pte_present(*pte) || !pte_dirty(*pte)
|| !pte_write(*pte)) {
pte_unmap_unlock(pte, ptl);
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)
--
2.35.3
next prev parent reply other threads:[~2023-06-08 19:16 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-08 19:07 [PATCH v2 00/23] arch: allow pte_offset_map[_lock]() to fail Hugh Dickins
2023-06-08 19:10 ` [PATCH v2 01/23] arm: " Hugh Dickins
2023-06-08 19:11 ` [PATCH v2 02/23] arm64: allow pte_offset_map() " Hugh Dickins
2023-06-08 19:13 ` [PATCH v2 03/23] arm64/hugetlb: pte_alloc_huge() pte_offset_huge() Hugh Dickins
2023-06-08 19:14 ` [PATCH v2 04/23] ia64/hugetlb: " Hugh Dickins
2023-06-08 19:15 ` Hugh Dickins [this message]
2023-06-08 19:16 ` [PATCH v2 06/23] microblaze: allow pte_offset_map() to fail Hugh Dickins
2023-06-08 19:17 ` [PATCH v2 07/23] mips: update_mmu_cache() can replace __update_tlb() Hugh Dickins
2023-06-09 8:08 ` [PATCH v2 07/23 fix] mips: update_mmu_cache() can replace __update_tlb(): fix Hugh Dickins
2023-06-14 23:17 ` [PATCH v2 07/23] mips: update_mmu_cache() can replace __update_tlb() Nathan Chancellor
2023-06-15 0:26 ` Hugh Dickins
2023-06-15 5:43 ` Hugh Dickins
2023-06-15 15:50 ` Nathan Chancellor
2023-06-15 21:22 ` Hugh Dickins
2023-06-15 23:02 ` [PATCH v2 07/23 replacement] mips: add pte_unmap() to balance pte_offset_map() Hugh Dickins
2023-06-17 3:54 ` Yu Zhao
2023-06-18 20:57 ` Yu Zhao
2023-06-15 22:07 ` [PATCH v2 07/23] mips: update_mmu_cache() can replace __update_tlb() Yu Zhao
2023-06-08 19:18 ` [PATCH v2 08/23] parisc: add pte_unmap() to balance get_ptep() Hugh Dickins
2023-06-19 3:55 ` Helge Deller
2023-06-08 19:20 ` [PATCH v2 09/23] parisc: unmap_uncached_pte() use pte_offset_kernel() Hugh Dickins
2023-06-08 19:21 ` [PATCH v2 10/23] parisc/hugetlb: pte_alloc_huge() pte_offset_huge() Hugh Dickins
2023-06-08 19:22 ` [PATCH v2 11/23] powerpc: kvmppc_unmap_free_pmd() pte_offset_kernel() Hugh Dickins
2023-06-08 19:23 ` [PATCH v2 12/23] powerpc: allow pte_offset_map[_lock]() to fail Hugh Dickins
2023-06-08 19:24 ` [PATCH v2 13/23] powerpc/hugetlb: pte_alloc_huge() Hugh Dickins
2023-06-08 19:25 ` [PATCH v2 14/23] riscv/hugetlb: pte_alloc_huge() pte_offset_huge() Hugh Dickins
2023-06-08 19:27 ` [PATCH v2 15/23] s390: allow pte_offset_map_lock() to fail Hugh Dickins
2023-06-13 11:45 ` Claudio Imbrenda
2023-06-08 19:29 ` [PATCH v2 16/23] s390: gmap use pte_unmap_unlock() not spin_unlock() Hugh Dickins
2023-06-08 19:30 ` [PATCH v2 17/23] sh/hugetlb: pte_alloc_huge() pte_offset_huge() Hugh Dickins
2023-06-08 19:31 ` [PATCH v2 18/23] sparc/hugetlb: " Hugh Dickins
2023-06-08 19:32 ` [PATCH v2 19/23] sparc: allow pte_offset_map() to fail Hugh Dickins
2023-06-08 19:33 ` [PATCH v2 20/23] sparc: iounit and iommu use pte_offset_kernel() Hugh Dickins
2023-06-08 19:35 ` [PATCH v2 21/23] x86: Allow get_locked_pte() to fail Hugh Dickins
2023-06-08 19:36 ` [PATCH v2 22/23] x86: sme_populate_pgd() use pte_offset_kernel() Hugh Dickins
2023-06-08 19:37 ` [PATCH v2 23/23] xtensa: add pte_unmap() to balance pte_offset_map() Hugh Dickins
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