diff mbox series

[v3] riscv/mm/fault: add show_pte() before die()

Message ID 20240723021820.87718-1-cuiyunhui@bytedance.com (mailing list archive)
State New
Headers show
Series [v3] riscv/mm/fault: add show_pte() before die() | expand

Checks

Context Check Description
conchuod/vmtest-for-next-PR success PR summary
conchuod/patch-1-test-1 success .github/scripts/patches/tests/build_rv32_defconfig.sh
conchuod/patch-1-test-2 success .github/scripts/patches/tests/build_rv64_clang_allmodconfig.sh
conchuod/patch-1-test-3 success .github/scripts/patches/tests/build_rv64_gcc_allmodconfig.sh
conchuod/patch-1-test-4 success .github/scripts/patches/tests/build_rv64_nommu_k210_defconfig.sh
conchuod/patch-1-test-5 success .github/scripts/patches/tests/build_rv64_nommu_virt_defconfig.sh
conchuod/patch-1-test-6 warning .github/scripts/patches/tests/checkpatch.sh
conchuod/patch-1-test-7 success .github/scripts/patches/tests/dtb_warn_rv64.sh
conchuod/patch-1-test-8 success .github/scripts/patches/tests/header_inline.sh
conchuod/patch-1-test-9 success .github/scripts/patches/tests/kdoc.sh
conchuod/patch-1-test-10 success .github/scripts/patches/tests/module_param.sh
conchuod/patch-1-test-11 success .github/scripts/patches/tests/verify_fixes.sh
conchuod/patch-1-test-12 success .github/scripts/patches/tests/verify_signedoff.sh

Commit Message

Yunhui Cui July 23, 2024, 2:18 a.m. UTC 
When the kernel displays "Unable to handle kernel paging request at
virtual address", we would like to confirm the status of the virtual
address in the page table. So add show_pte() before die().

Signed-off-by: Yunhui Cui <cuiyunhui@bytedance.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
---
 arch/riscv/mm/fault.c | 52 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 52 insertions(+)

Comments

Yunhui Cui Aug. 15, 2024, 2:05 a.m. UTC | #1 
Hi All,

A gentle ping, Any more comments on this patch?

On Tue, Jul 23, 2024 at 10:18 AM Yunhui Cui <cuiyunhui@bytedance.com> wrote:
>
> When the kernel displays "Unable to handle kernel paging request at
> virtual address", we would like to confirm the status of the virtual
> address in the page table. So add show_pte() before die().
>
> Signed-off-by: Yunhui Cui <cuiyunhui@bytedance.com>
> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
> Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
> ---
>  arch/riscv/mm/fault.c | 52 +++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 52 insertions(+)
>
> diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
> index 5224f3733802..c72e6c7c09ef 100644
> --- a/arch/riscv/mm/fault.c
> +++ b/arch/riscv/mm/fault.c
> @@ -22,6 +22,57 @@
>
>  #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 +82,7 @@ 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);
>  }
> --
> 2.39.2
>

Thanks,
Yunhui
Yunhui Cui Sept. 18, 2024, 3:44 a.m. UTC | #2 
Hi Palmer,

A gentle ping for this patch.

On Thu, Aug 15, 2024 at 10:05 AM yunhui cui <cuiyunhui@bytedance.com> wrote:
>
> Hi All,
>
> A gentle ping, Any more comments on this patch?
>
> On Tue, Jul 23, 2024 at 10:18 AM Yunhui Cui <cuiyunhui@bytedance.com> wrote:
> >
> > When the kernel displays "Unable to handle kernel paging request at
> > virtual address", we would like to confirm the status of the virtual
> > address in the page table. So add show_pte() before die().
> >
> > Signed-off-by: Yunhui Cui <cuiyunhui@bytedance.com>
> > Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
> > Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
> > ---
> >  arch/riscv/mm/fault.c | 52 +++++++++++++++++++++++++++++++++++++++++++
> >  1 file changed, 52 insertions(+)
> >
> > diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
> > index 5224f3733802..c72e6c7c09ef 100644
> > --- a/arch/riscv/mm/fault.c
> > +++ b/arch/riscv/mm/fault.c
> > @@ -22,6 +22,57 @@
> >
> >  #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 +82,7 @@ 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);
> >  }
> > --
> > 2.39.2
> >
>
> Thanks,
> Yunhui


Thanks,
Yunhui
diff mbox series

Patch

diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
index 5224f3733802..c72e6c7c09ef 100644
--- a/arch/riscv/mm/fault.c
+++ b/arch/riscv/mm/fault.c
@@ -22,6 +22,57 @@ 
 
 #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 +82,7 @@  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);
 }