[PATCH v2 19/23] sparc: allow pte_offset_map() to fail
From: Hugh Dickins <hughd@google.com>
Date: 2023-06-08 19:32:49
Also in:
linux-arm-kernel, linux-m68k, linux-mips, linux-mm, linux-riscv, linux-s390, linux-sh, lkml, sparclinux
Subsystem:
sparc + ultrasparc (sparc/sparc64), the rest · Maintainers:
"David S. Miller", Andreas Larsson, Linus Torvalds
In rare transient cases, not yet made possible, pte_offset_map() and pte_offset_map_lock() may not find a page table: handle appropriately. Signed-off-by: Hugh Dickins <hughd@google.com> --- arch/sparc/kernel/signal32.c | 2 ++ arch/sparc/mm/fault_64.c | 3 +++ arch/sparc/mm/tlb.c | 2 ++ 3 files changed, 7 insertions(+)
diff --git a/arch/sparc/kernel/signal32.c b/arch/sparc/kernel/signal32.c
index dad38960d1a8..ca450c7bc53f 100644
--- a/arch/sparc/kernel/signal32.c
+++ b/arch/sparc/kernel/signal32.c@@ -328,6 +328,8 @@ static void flush_signal_insns(unsigned long address) goto out_irqs_on; ptep = pte_offset_map(pmdp, address); + if (!ptep) + goto out_irqs_on; pte = *ptep; if (!pte_present(pte)) goto out_unmap;
diff --git a/arch/sparc/mm/fault_64.c b/arch/sparc/mm/fault_64.c
index d91305de694c..d8a407fbe350 100644
--- a/arch/sparc/mm/fault_64.c
+++ b/arch/sparc/mm/fault_64.c@@ -99,6 +99,7 @@ static unsigned int get_user_insn(unsigned long tpc) local_irq_disable(); pmdp = pmd_offset(pudp, tpc); +again: if (pmd_none(*pmdp) || unlikely(pmd_bad(*pmdp))) goto out_irq_enable;
@@ -115,6 +116,8 @@ static unsigned int get_user_insn(unsigned long tpc) #endif { ptep = pte_offset_map(pmdp, tpc); + if (!ptep) + goto again; pte = *ptep; if (pte_present(pte)) { pa = (pte_pfn(pte) << PAGE_SHIFT);
diff --git a/arch/sparc/mm/tlb.c b/arch/sparc/mm/tlb.c
index 9a725547578e..7ecf8556947a 100644
--- a/arch/sparc/mm/tlb.c
+++ b/arch/sparc/mm/tlb.c@@ -149,6 +149,8 @@ static void tlb_batch_pmd_scan(struct mm_struct *mm, unsigned long vaddr, pte_t *pte; pte = pte_offset_map(&pmd, vaddr); + if (!pte) + return; end = vaddr + HPAGE_SIZE; while (vaddr < end) { if (pte_val(*pte) & _PAGE_VALID) {
--
2.35.3