Date: Wed, 6 Apr 2022 22:38:40 +0800
From: Rongwei Wang <rongwei.wang@linux.alibaba.com>
To: crash-utility@redhat.com, k-hagio-ab@nec.com,
shijie@os.amperecomputing.com, piliu@redhat.com
Subject: [Crash-utility] [PATCH v2] arm64: handle 1GB block for
VM_L4_4K
Message-ID: <20220406143840.76523-1-rongwei.wang@linux.alibaba.com>
Content-Type: text/plain; charset="US-ASCII"; x-default=true
When arm64 is configured with PAGE_SIZE=4k and 4 level
translation, the pagetable of all pages may be created with
block mapping or contiguous mapping as much as possible, likes
disable CONFIG_RODATA_FULL_DEFAULT_ENABLED. But now, vtop
command can not handle 1GB block (PUD mapping) well, and just
shows a seek error:
crash> vtop ffff00184a800000
VIRTUAL PHYSICAL
ffff00184a800000 188a800000
PAGE DIRECTORY: ffff8000110aa000
PGD: ffff8000110aa000 => 203fff9003
PUD: ffff001fffff9308 => 68001880000705
PMD: ffff0018400002a0 => ffff8000103b4fd0
vtop: seek error: kernel virtual address: ffff7fffd03b4000 type: "page table"
This patch fixes it, and shows as following:
crash> vtop ffff00184a800000
VIRTUAL PHYSICAL
ffff00184a800000 188a800000
PAGE DIRECTORY: ffff8000110aa000
PGD: ffff8000110aa000 => 203fff9003
PUD: ffff001fffff9308 => 68001880000705
PAGE: 1880000000 (1GB)
PTE PHYSICAL FLAGS
68001880000705 1880000000 (VALID|SHARED|AF|PXN|UXN)
PAGE PHYSICAL MAPPING INDEX CNT FLAGS
fffffe00610a0000 188a800000 0 0 0 77fffe0000000000
Acked-by: Kazuhito Hagio <k-hagio-ab@nec.com>
Signed-off-by: Rongwei Wang <rongwei.wang@linux.alibaba.com>
---
arm64.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/arm64.c b/arm64.c
index 2177c52..65f6cdf 100644
--- a/arm64.c
+++ b/arm64.c
@@ -1999,6 +1999,16 @@ arm64_vtop_4level_4k(ulong pgd, ulong vaddr, physaddr_t *paddr, int verbose)
if (!pud_val)
goto no_page;
+ if ((pud_val & PUD_TYPE_MASK) == PUD_TYPE_SECT) {
+ ulong sectionbase = (pud_val & SECTION_PAGE_MASK_1GB) & PHYS_MASK;
+ if (verbose) {
+ fprintf(fp, " PAGE: %lx (1GB)\n\n", sectionbase);
+ arm64_translate_pte(pud_val, 0, 0);
+ }
+ *paddr = sectionbase + (vaddr & ~SECTION_PAGE_MASK_1GB);
+ return TRUE;
+ }
+
pmd_base = (ulong *)PTOV(pud_val & PHYS_MASK & (s32)machdep->pagemask);
FILL_PMD(pmd_base, KVADDR, PTRS_PER_PMD_L4_4K * sizeof(ulong));
pmd_ptr = pmd_base + (((vaddr) >> PMD_SHIFT_L4_4K) & (PTRS_PER_PMD_L4_4K - 1));
--
Thank you for the fix.
The v2 looks good to me. Applied.
Thanks.
Lianbo
2.27.0