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Diffstat (limited to 'arch/riscv/mm/fault.c')
-rw-r--r--arch/riscv/mm/fault.c109
1 files changed, 86 insertions, 23 deletions
diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
index 6ea2cce4cc17..04ed6f8acae4 100644
--- a/arch/riscv/mm/fault.c
+++ b/arch/riscv/mm/fault.c
@@ -20,8 +20,62 @@
#include <asm/ptrace.h>
#include <asm/tlbflush.h>
+#define CREATE_TRACE_POINTS
+#include <trace/events/exceptions.h>
+
#include "../kernel/head.h"
+static void show_pte(unsigned long addr)
+{
+ pgd_t *pgdp, pgd;
+ p4d_t *p4dp, p4d;
+ pud_t *pudp, pud;
+ pmd_t *pmdp, pmd;
+ pte_t *ptep, pte;
+ struct mm_struct *mm = current->mm;
+
+ if (!mm)
+ mm = &init_mm;
+
+ pr_alert("Current %s pgtable: %luK pagesize, %d-bit VAs, pgdp=0x%016llx\n",
+ current->comm, PAGE_SIZE / SZ_1K, VA_BITS,
+ mm == &init_mm ? (u64)__pa_symbol(mm->pgd) : virt_to_phys(mm->pgd));
+
+ pgdp = pgd_offset(mm, addr);
+ pgd = pgdp_get(pgdp);
+ pr_alert("[%016lx] pgd=%016lx", addr, pgd_val(pgd));
+ if (pgd_none(pgd) || pgd_bad(pgd) || pgd_leaf(pgd))
+ goto out;
+
+ p4dp = p4d_offset(pgdp, addr);
+ p4d = p4dp_get(p4dp);
+ pr_cont(", p4d=%016lx", p4d_val(p4d));
+ if (p4d_none(p4d) || p4d_bad(p4d) || p4d_leaf(p4d))
+ goto out;
+
+ pudp = pud_offset(p4dp, addr);
+ pud = pudp_get(pudp);
+ pr_cont(", pud=%016lx", pud_val(pud));
+ if (pud_none(pud) || pud_bad(pud) || pud_leaf(pud))
+ goto out;
+
+ pmdp = pmd_offset(pudp, addr);
+ pmd = pmdp_get(pmdp);
+ pr_cont(", pmd=%016lx", pmd_val(pmd));
+ if (pmd_none(pmd) || pmd_bad(pmd) || pmd_leaf(pmd))
+ goto out;
+
+ ptep = pte_offset_map(pmdp, addr);
+ if (!ptep)
+ goto out;
+
+ pte = ptep_get(ptep);
+ pr_cont(", pte=%016lx", pte_val(pte));
+ pte_unmap(ptep);
+out:
+ pr_cont("\n");
+}
+
static void die_kernel_fault(const char *msg, unsigned long addr,
struct pt_regs *regs)
{
@@ -31,6 +85,7 @@ static void die_kernel_fault(const char *msg, unsigned long addr,
addr);
bust_spinlocks(0);
+ show_pte(addr);
die(regs, "Oops");
make_task_dead(SIGKILL);
}
@@ -61,26 +116,27 @@ static inline void no_context(struct pt_regs *regs, unsigned long addr)
static inline void mm_fault_error(struct pt_regs *regs, unsigned long addr, vm_fault_t fault)
{
+ if (!user_mode(regs)) {
+ no_context(regs, addr);
+ return;
+ }
+
if (fault & VM_FAULT_OOM) {
/*
* We ran out of memory, call the OOM killer, and return the userspace
* (which will retry the fault, or kill us if we got oom-killed).
*/
- if (!user_mode(regs)) {
- no_context(regs, addr);
- return;
- }
pagefault_out_of_memory();
return;
- } else if (fault & VM_FAULT_SIGBUS) {
+ } else if (fault & (VM_FAULT_SIGBUS | VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE)) {
/* Kernel mode? Handle exceptions or die */
- if (!user_mode(regs)) {
- no_context(regs, addr);
- return;
- }
do_trap(regs, SIGBUS, BUS_ADRERR, addr);
return;
+ } else if (fault & VM_FAULT_SIGSEGV) {
+ do_trap(regs, SIGSEGV, SEGV_MAPERR, addr);
+ return;
}
+
BUG();
}
@@ -136,24 +192,24 @@ static inline void vmalloc_fault(struct pt_regs *regs, int code, unsigned long a
pgd = (pgd_t *)pfn_to_virt(pfn) + index;
pgd_k = init_mm.pgd + index;
- if (!pgd_present(*pgd_k)) {
+ if (!pgd_present(pgdp_get(pgd_k))) {
no_context(regs, addr);
return;
}
- set_pgd(pgd, *pgd_k);
+ set_pgd(pgd, pgdp_get(pgd_k));
p4d_k = p4d_offset(pgd_k, addr);
- if (!p4d_present(*p4d_k)) {
+ if (!p4d_present(p4dp_get(p4d_k))) {
no_context(regs, addr);
return;
}
pud_k = pud_offset(p4d_k, addr);
- if (!pud_present(*pud_k)) {
+ if (!pud_present(pudp_get(pud_k))) {
no_context(regs, addr);
return;
}
- if (pud_leaf(*pud_k))
+ if (pud_leaf(pudp_get(pud_k)))
goto flush_tlb;
/*
@@ -161,11 +217,11 @@ static inline void vmalloc_fault(struct pt_regs *regs, int code, unsigned long a
* to copy individual PTEs
*/
pmd_k = pmd_offset(pud_k, addr);
- if (!pmd_present(*pmd_k)) {
+ if (!pmd_present(pmdp_get(pmd_k))) {
no_context(regs, addr);
return;
}
- if (pmd_leaf(*pmd_k))
+ if (pmd_leaf(pmdp_get(pmd_k)))
goto flush_tlb;
/*
@@ -175,7 +231,7 @@ static inline void vmalloc_fault(struct pt_regs *regs, int code, unsigned long a
* silently loop forever.
*/
pte_k = pte_offset_kernel(pmd_k, addr);
- if (!pte_present(*pte_k)) {
+ if (!pte_present(ptep_get(pte_k))) {
no_context(regs, addr);
return;
}
@@ -238,6 +294,11 @@ void handle_page_fault(struct pt_regs *regs)
if (kprobe_page_fault(regs, cause))
return;
+ if (user_mode(regs))
+ trace_page_fault_user(addr, regs, cause);
+ else
+ trace_page_fault_kernel(addr, regs, cause);
+
/*
* Fault-in kernel-space virtual memory on-demand.
* The 'reference' page table is init_mm.pgd.
@@ -283,7 +344,6 @@ void handle_page_fault(struct pt_regs *regs)
flags |= FAULT_FLAG_WRITE;
else if (cause == EXC_INST_PAGE_FAULT)
flags |= FAULT_FLAG_INSTRUCTION;
-#ifdef CONFIG_PER_VMA_LOCK
if (!(flags & FAULT_FLAG_USER))
goto lock_mmap;
@@ -293,17 +353,23 @@ void handle_page_fault(struct pt_regs *regs)
if (unlikely(access_error(cause, vma))) {
vma_end_read(vma);
- goto lock_mmap;
+ count_vm_vma_lock_event(VMA_LOCK_SUCCESS);
+ tsk->thread.bad_cause = cause;
+ bad_area_nosemaphore(regs, SEGV_ACCERR, addr);
+ return;
}
fault = handle_mm_fault(vma, addr, flags | FAULT_FLAG_VMA_LOCK, regs);
- vma_end_read(vma);
+ if (!(fault & (VM_FAULT_RETRY | VM_FAULT_COMPLETED)))
+ vma_end_read(vma);
if (!(fault & VM_FAULT_RETRY)) {
count_vm_vma_lock_event(VMA_LOCK_SUCCESS);
goto done;
}
count_vm_vma_lock_event(VMA_LOCK_RETRY);
+ if (fault & VM_FAULT_MAJOR)
+ flags |= FAULT_FLAG_TRIED;
if (fault_signal_pending(fault, regs)) {
if (!user_mode(regs))
@@ -311,7 +377,6 @@ void handle_page_fault(struct pt_regs *regs)
return;
}
lock_mmap:
-#endif /* CONFIG_PER_VMA_LOCK */
retry:
vma = lock_mm_and_find_vma(mm, addr, regs);
@@ -368,9 +433,7 @@ retry:
mmap_read_unlock(mm);
-#ifdef CONFIG_PER_VMA_LOCK
done:
-#endif
if (unlikely(fault & VM_FAULT_ERROR)) {
tsk->thread.bad_cause = cause;
mm_fault_error(regs, addr, fault);
generated by cgit (git 2.34.1) at 2025-12-25 02:28:44 +0000