----- Original Message ----- > Hi Jim, > > The problem looks to be the use of PAGEOFFSET() into the 512-byte pgd used > for 3-level/64K-pages: I've committed a fix for crash-7.1.6: https://github.com/crash-utility/crash/commit/ac080651b6fc0e3c8c67d69876222853db30bf7c Fix for the introduction of ARM64 support for 64K pages with 3-level page tables in crash-7.1.5, which fails to translate user space virtual addresses. Without the patch, "vtop <user-space address>" fails to translate all user-space addresses, and any command that needs to either translate or read user-space memory, such as "vm -p", "ps -a", and "rd -u" will fail. (anderson@xxxxxxxxxx) Dave > > static int > arm64_vtop_3level_64k(ulong pgd, ulong vaddr, physaddr_t *paddr, int verbose) > { > ulong *pgd_base, *pgd_ptr, pgd_val; > ulong *pmd_base, *pmd_ptr, pmd_val; > ulong *pte_base, *pte_ptr, pte_val; > > if (verbose) > fprintf(fp, "PAGE DIRECTORY: %lx\n", pgd); > > pgd_base = (ulong *)pgd; > FILL_PGD(pgd_base, KVADDR, PTRS_PER_PGD_L3_64K * sizeof(ulong)); > pgd_ptr = pgd_base + (((vaddr) >> PGDIR_SHIFT_L3_64K) & > (PTRS_PER_PGD_L3_64K - 1)); > pgd_val = ULONG(machdep->pgd + PAGEOFFSET(pgd_ptr)); > ^^^^^^^^^^^^^^^^^^ > > For kernel vmalloc addresses, the kernel's "swapper_pg_dir" is used, which > has a base > address that's aligned on a 64k page boundary. So PAGEOFFSET() works as an > index. > > But for user-space addresses, the mm_struct->pgd is not 64K page aligned so > the > use of PAGEOFFSET() calculates an address that's goes way beyond the end of > the > 512-byte aligned pgd: > > crash> for user vm -p | grep -e PGD -e "k " > MM PGD RSS TOTAL_VM > ffff8003d61ec240 ffff8003d5b12c00 11904k 12992k > MM PGD RSS TOTAL_VM > ffff8003d60aec40 ffff8003dcb7ca00 4864k 88448k > MM PGD RSS TOTAL_VM > ffff8000dbf1dc80 ffff8003d69bca00 8704k 92928k > MM PGD RSS TOTAL_VM > ffff8000dbf1e700 ffff8003d69b4a00 8768k 17536k > MM PGD RSS TOTAL_VM > ffff8003d65c9300 ffff8000d4055600 5696k 16576k > MM PGD RSS TOTAL_VM > ffff8003d65c9300 ffff8000d4055600 5696k 16576k > MM PGD RSS TOTAL_VM > ffff8003d65c9840 ffff8000d4051800 1664k 2560k > MM PGD RSS TOTAL_VM > ffff8003d60a8340 ffff8003dcb7fa00 10944k 303552k > MM PGD RSS TOTAL_VM > ffff8003d65c8880 ffff8000d4052c00 19456k 353600k > MM PGD RSS TOTAL_VM > ffff8003d61ab7c0 ffff8003dc86b800 4864k 14016k > MM PGD RSS TOTAL_VM > ffff8000dbf18340 ffff8003d69b1400 7424k 157632k > MM PGD RSS TOTAL_VM > ffff8003d60a8340 ffff8003dcb7fa00 10944k 303552k > MM PGD RSS TOTAL_VM > ffff8003d60a8340 ffff8003dcb7fa00 10944k 303552k > MM PGD RSS TOTAL_VM > ffff8000dbf18340 ffff8003d69b1400 7424k 157632k > MM PGD RSS TOTAL_VM > ffff8000dbf18340 ffff8003d69b1400 7424k 157632k > MM PGD RSS TOTAL_VM > ffff8000dbf18340 ffff8003d69b1400 7424k 157632k > MM PGD RSS TOTAL_VM > ffff8000dbf18340 ffff8003d69b1400 7424k 157632k > MM PGD RSS TOTAL_VM > ffff8000dbf18340 ffff8003d69b1400 7424k 157632k > MM PGD RSS TOTAL_VM > ffff8003d61ab7c0 ffff8003dc86b800 4864k 14016k > MM PGD RSS TOTAL_VM > ffff8000c403b7c0 ffff8003d6597800 4928k 5888k > MM PGD RSS TOTAL_VM > ffff8003d59db7c0 ffff8003dcd18600 4352k 5248k > MM PGD RSS TOTAL_VM > ffff8003d61ead40 ffff8003d4107400 3776k 5760k > MM PGD RSS TOTAL_VM > ffff8000c403ad40 ffff8003d6592000 4224k 5120k > MM PGD RSS TOTAL_VM > ffff8003d60a78c0 ffff8003dcb72600 2496k 109888k > MM PGD RSS TOTAL_VM > ffff8003d61a8880 ffff8003dc86b200 2176k 109888k > MM PGD RSS TOTAL_VM > ffff8003d65c8880 ffff8000d4052c00 19456k 353600k > MM PGD RSS TOTAL_VM > ffff8003d65c8880 ffff8000d4052c00 19456k 353600k > ... > > Dave > > > > ----- Original Message ----- > > > > ----- Original Message ----- > > > > Adds ARM64 support for 3-level page tables with 64K pages and 48 VA > > > > bits. > > > > > > Nicely done, Jim. Queued for crash-7.1.5: > > > > > > https://github.com/crash-utility/crash/commit/ab91852f945bfecfa0bca6a42253fbecb38723db > > > > > > Thanks, > > > Dave > > > > > > > Hi Jim, > > > > I just noticed today that your 3-level 64K patch does not work for user > > virtual address space. > > I haven't looked too deeply into it, but for example on a live system, all > > user virtual address > > vtop operations fail, all disk-backed user memory space shows the "FILE:" > > backing, and the > > anonymous space shows "(not mapped)": > > > > crash> help -m | grep VM > > flags: 10400069 > > (KSYMS_START|VM_L3_64K|VMEMMAP|KDUMP_ENABLED|IRQ_STACKS|MACHDEP_BT_TEXT) > > crash> sys | grep RELEASE > > RELEASE: 4.5.0-0.38.el7.aarch64 > > crash> set > > PID: 1212 > > COMMAND: "crash" > > TASK: ffff8003d74f3f00 [THREAD_INFO: ffff8003d7454000] > > CPU: 1 > > STATE: TASK_RUNNING (ACTIVE) > > crash> vm -p > > PID: 1212 TASK: ffff8003d74f3f00 CPU: 1 COMMAND: "crash" > > MM PGD RSS TOTAL_VM > > ffff8000c40363c0 ffff8003db6a9200 211904k 355264k > > VMA START END FLAGS FILE > > ffff8003de746d40 400000 a00000 875 /root/crash.git/crash > > VIRTUAL PHYSICAL > > 400000 FILE: /root/crash.git/crash OFFSET: 0 > > 410000 FILE: /root/crash.git/crash OFFSET: 10000 > > 420000 FILE: /root/crash.git/crash OFFSET: 20000 > > 430000 FILE: /root/crash.git/crash OFFSET: 30000 > > 440000 FILE: /root/crash.git/crash OFFSET: 40000 > > 450000 FILE: /root/crash.git/crash OFFSET: 50000 > > ... [ cut ] ... > > VMA START END FLAGS FILE > > ffff8003de745d70 a50000 b00000 100073 > > VIRTUAL PHYSICAL > > a50000 (not mapped) > > a60000 (not mapped) > > a70000 (not mapped) > > a80000 (not mapped) > > a90000 (not mapped) > > aa0000 (not mapped) > > ab0000 (not mapped) > > ac0000 (not mapped) > > ... > > > > In all cases, the PGD value reads as 0 and therefore fails: > > > > crash> vtop 400000 > > VIRTUAL PHYSICAL > > 400000 (not mapped) > > > > PAGE DIRECTORY: ffff8003db6a9200 > > PGD: ffff8003db6a9200 => 0 > > > > VMA START END FLAGS FILE > > ffff8003de746d40 400000 a00000 875 /root/crash.git/crash > > > > FILE: /root/crash.git/crash OFFSET: 0 > > > > crash> > > > > That is the correct PGD address, and when read, it looks like a valid PTE: > > > > crash> rd ffff8003db6a9200 > > ffff8003db6a9200: 00000043dee60003 ....C... > > crash> > > > > vmalloc() addresses translate just fine, and since they use the same > > function, > > I'm not sure what's going on? Did you ever check user-space translations? > > > > Thanks, > > Dave > > > > > > > > > > > > > > > > --- > > > > arm64.c | 126 > > > > ++++++++++++++++++++++++++++++++++++++++++++++++++++++++-------- > > > > defs.h | 28 +++++++++++---- > > > > 2 files changed, 133 insertions(+), 21 deletions(-) > > > > > > > > diff --git a/arm64.c b/arm64.c > > > > index f6ea7a1..d1c9c3e 100644 > > > > --- a/arm64.c > > > > +++ b/arm64.c > > > > @@ -34,6 +34,7 @@ static void arm64_init_kernel_pgd(void); > > > > static int arm64_kvtop(struct task_context *, ulong, physaddr_t *, > > > > int); > > > > static int arm64_uvtop(struct task_context *, ulong, physaddr_t *, > > > > int); > > > > static int arm64_vtop_2level_64k(ulong, ulong, physaddr_t *, int); > > > > +static int arm64_vtop_3level_64k(ulong, ulong, physaddr_t *, int); > > > > static int arm64_vtop_3level_4k(ulong, ulong, physaddr_t *, int); > > > > static ulong arm64_get_task_pgd(ulong); > > > > static void arm64_irq_stack_init(void); > > > > @@ -188,15 +189,29 @@ arm64_init(int when) > > > > break; > > > > > > > > case 65536: > > > > - machdep->flags |= VM_L2_64K; > > > > - machdep->ptrs_per_pgd = PTRS_PER_PGD_L2_64K; > > > > - if ((machdep->pgd = > > > > - (char *)malloc(PTRS_PER_PGD_L2_64K * 8)) == NULL) > > > > - error(FATAL, "cannot malloc pgd space."); > > > > - if ((machdep->ptbl = > > > > - (char *)malloc(PTRS_PER_PTE_L2_64K * 8)) == NULL) > > > > - error(FATAL, "cannot malloc ptbl space."); > > > > - machdep->pmd = NULL; /* not used */ > > > > + if (machdep->machspec->VA_BITS > PGDIR_SHIFT_L3_64K) { > > > > + machdep->flags |= VM_L3_64K; > > > > + machdep->ptrs_per_pgd = PTRS_PER_PGD_L3_64K; > > > > + if ((machdep->pgd = > > > > + (char *)malloc(PTRS_PER_PGD_L3_64K * 8)) == NULL) > > > > + error(FATAL, "cannot malloc pgd space."); > > > > + if ((machdep->pmd = > > > > + (char *)malloc(PTRS_PER_PMD_L3_64K * 8)) == NULL) > > > > + error(FATAL, "cannot malloc pmd space."); > > > > + if ((machdep->ptbl = > > > > + (char *)malloc(PTRS_PER_PTE_L3_64K * 8)) == NULL) > > > > + error(FATAL, "cannot malloc ptbl space."); > > > > + } else { > > > > + machdep->flags |= VM_L2_64K; > > > > + machdep->ptrs_per_pgd = PTRS_PER_PGD_L2_64K; > > > > + if ((machdep->pgd = > > > > + (char *)malloc(PTRS_PER_PGD_L2_64K * 8)) == NULL) > > > > + error(FATAL, "cannot malloc pgd space."); > > > > + if ((machdep->ptbl = > > > > + (char *)malloc(PTRS_PER_PTE_L2_64K * 8)) == NULL) > > > > + error(FATAL, "cannot malloc ptbl space."); > > > > + machdep->pmd = NULL; /* not used */ > > > > + } > > > > machdep->pud = NULL; /* not used */ > > > > break; > > > > > > > > @@ -379,6 +394,8 @@ arm64_dump_machdep_table(ulong arg) > > > > fprintf(fp, "%sPHYS_OFFSET", others++ ? "|" : ""); > > > > if (machdep->flags & VM_L2_64K) > > > > fprintf(fp, "%sVM_L2_64K", others++ ? "|" : ""); > > > > + if (machdep->flags & VM_L3_64K) > > > > + fprintf(fp, "%sVM_L3_64K", others++ ? "|" : ""); > > > > if (machdep->flags & VM_L3_4K) > > > > fprintf(fp, "%sVM_L3_4K", others++ ? "|" : ""); > > > > if (machdep->flags & VMEMMAP) > > > > @@ -410,10 +427,14 @@ arm64_dump_machdep_table(ulong arg) > > > > fprintf(fp, " processor_speed: arm64_processor_speed()\n"); > > > > fprintf(fp, " uvtop: arm64_uvtop()->%s()\n", > > > > machdep->flags & VM_L3_4K ? > > > > - "arm64_vtop_3level_4k" : "arm64_vtop_2level_64k"); > > > > + "arm64_vtop_3level_4k" : > > > > + machdep->flags & VM_L3_64K ? > > > > + "arm64_vtop_3level_64k" : "arm64_vtop_2level_64k"); > > > > fprintf(fp, " kvtop: arm64_kvtop()->%s()\n", > > > > machdep->flags & VM_L3_4K ? > > > > - "arm64_vtop_3level_4k" : "arm64_vtop_2level_64k"); > > > > + "arm64_vtop_3level_4k" : > > > > + machdep->flags & VM_L3_64K ? > > > > + "arm64_vtop_3level_64k" : "arm64_vtop_2level_64k"); > > > > fprintf(fp, " get_task_pgd: arm64_get_task_pgd()\n"); > > > > fprintf(fp, " dump_irq: generic_dump_irq()\n"); > > > > fprintf(fp, " get_stack_frame: arm64_get_stack_frame()\n"); > > > > @@ -719,10 +740,12 @@ arm64_kvtop(struct task_context *tc, ulong > > > > kvaddr, > > > > physaddr_t *paddr, int verbos > > > > kernel_pgd = vt->kernel_pgd[0]; > > > > *paddr = 0; > > > > > > > > - switch (machdep->flags & (VM_L2_64K|VM_L3_4K)) > > > > + switch (machdep->flags & (VM_L2_64K|VM_L3_64K|VM_L3_4K)) > > > > { > > > > case VM_L2_64K: > > > > return arm64_vtop_2level_64k(kernel_pgd, kvaddr, paddr, verbose); > > > > + case VM_L3_64K: > > > > + return arm64_vtop_3level_64k(kernel_pgd, kvaddr, paddr, verbose); > > > > case VM_L3_4K: > > > > return arm64_vtop_3level_4k(kernel_pgd, kvaddr, paddr, verbose); > > > > default: > > > > @@ -740,10 +763,12 @@ arm64_uvtop(struct task_context *tc, ulong > > > > uvaddr, > > > > physaddr_t *paddr, int verbos > > > > > > > > *paddr = 0; > > > > > > > > - switch (machdep->flags & (VM_L2_64K|VM_L3_4K)) > > > > + switch (machdep->flags & (VM_L2_64K|VM_L3_64K|VM_L3_4K)) > > > > { > > > > case VM_L2_64K: > > > > return arm64_vtop_2level_64k(user_pgd, uvaddr, paddr, verbose); > > > > + case VM_L3_64K: > > > > + return arm64_vtop_3level_64k(user_pgd, uvaddr, paddr, verbose); > > > > case VM_L3_4K: > > > > return arm64_vtop_3level_4k(user_pgd, uvaddr, paddr, verbose); > > > > default: > > > > @@ -820,6 +845,78 @@ no_page: > > > > return FALSE; > > > > } > > > > > > > > +static int > > > > +arm64_vtop_3level_64k(ulong pgd, ulong vaddr, physaddr_t *paddr, int > > > > verbose) > > > > +{ > > > > + ulong *pgd_base, *pgd_ptr, pgd_val; > > > > + ulong *pmd_base, *pmd_ptr, pmd_val; > > > > + ulong *pte_base, *pte_ptr, pte_val; > > > > + > > > > + if (verbose) > > > > + fprintf(fp, "PAGE DIRECTORY: %lx\n", pgd); > > > > + > > > > + pgd_base = (ulong *)pgd; > > > > + FILL_PGD(pgd_base, KVADDR, PTRS_PER_PGD_L3_64K * sizeof(ulong)); > > > > + pgd_ptr = pgd_base + (((vaddr) >> PGDIR_SHIFT_L3_64K) & > > > > (PTRS_PER_PGD_L3_64K - 1)); > > > > + pgd_val = ULONG(machdep->pgd + PAGEOFFSET(pgd_ptr)); > > > > + if (verbose) > > > > + fprintf(fp, " PGD: %lx => %lx\n", (ulong)pgd_ptr, > > > > pgd_val); > > > > + if (!pgd_val) > > > > + goto no_page; > > > > + > > > > + /* > > > > + * #define __PAGETABLE_PUD_FOLDED > > > > + */ > > > > + > > > > + pmd_base = (ulong *)PTOV(pgd_val & PHYS_MASK & > > > > (s32)machdep->pagemask); > > > > + FILL_PMD(pmd_base, KVADDR, PTRS_PER_PMD_L3_64K * sizeof(ulong)); > > > > + pmd_ptr = pmd_base + (((vaddr) >> PMD_SHIFT_L3_64K) & > > > > (PTRS_PER_PMD_L3_64K > > > > - 1)); > > > > + pmd_val = ULONG(machdep->pmd + PAGEOFFSET(pmd_ptr)); > > > > + if (verbose) > > > > + fprintf(fp, " PMD: %lx => %lx\n", (ulong)pmd_ptr, > > > > pmd_val); > > > > + if (!pmd_val) > > > > + goto no_page; > > > > + > > > > + if ((pmd_val & PMD_TYPE_MASK) == PMD_TYPE_SECT) { > > > > + ulong sectionbase = (pmd_val & SECTION_PAGE_MASK_512MB) & PHYS_MASK; > > > > + if (verbose) { > > > > + fprintf(fp, " PAGE: %lx (512MB)\n\n", sectionbase); > > > > + arm64_translate_pte(pmd_val, 0, 0); > > > > + } > > > > + *paddr = sectionbase + (vaddr & ~SECTION_PAGE_MASK_512MB); > > > > + return TRUE; > > > > + } > > > > + > > > > + pte_base = (ulong *)PTOV(pmd_val & PHYS_MASK & > > > > (s32)machdep->pagemask); > > > > + FILL_PTBL(pte_base, KVADDR, PTRS_PER_PTE_L3_64K * sizeof(ulong)); > > > > + pte_ptr = pte_base + (((vaddr) >> machdep->pageshift) & > > > > (PTRS_PER_PTE_L3_64K - 1)); > > > > + pte_val = ULONG(machdep->ptbl + PAGEOFFSET(pte_ptr)); > > > > + if (verbose) > > > > + fprintf(fp, " PTE: %lx => %lx\n", (ulong)pte_ptr, > > > > pte_val); > > > > + if (!pte_val) > > > > + goto no_page; > > > > + > > > > + if (pte_val & PTE_VALID) { > > > > + *paddr = (PAGEBASE(pte_val) & PHYS_MASK) + PAGEOFFSET(vaddr); > > > > + if (verbose) { > > > > + fprintf(fp, " PAGE: %lx\n\n", PAGEBASE(*paddr)); > > > > + arm64_translate_pte(pte_val, 0, 0); > > > > + } > > > > + } else { > > > > + if (IS_UVADDR(vaddr, NULL)) > > > > + *paddr = pte_val; > > > > + if (verbose) { > > > > + fprintf(fp, "\n"); > > > > + arm64_translate_pte(pte_val, 0, 0); > > > > + } > > > > + goto no_page; > > > > + } > > > > + > > > > + return TRUE; > > > > +no_page: > > > > + return FALSE; > > > > +} > > > > + > > > > static int > > > > arm64_vtop_3level_4k(ulong pgd, ulong vaddr, physaddr_t *paddr, int > > > > verbose) > > > > { > > > > @@ -2348,9 +2445,10 @@ arm64_calc_virtual_memory_ranges(void) > > > > > > > > STRUCT_SIZE_INIT(page, "page"); > > > > > > > > - switch (machdep->flags & (VM_L2_64K|VM_L3_4K)) > > > > + switch (machdep->flags & (VM_L2_64K|VM_L3_64K|VM_L3_4K)) > > > > { > > > > case VM_L2_64K: > > > > + case VM_L3_64K: > > > > PUD_SIZE = PGDIR_SIZE_L2_64K; > > > > break; > > > > case VM_L3_4K: > > > > diff --git a/defs.h b/defs.h > > > > index 56ae06c..d1b49d0 100644 > > > > --- a/defs.h > > > > +++ b/defs.h > > > > @@ -2815,7 +2815,7 @@ typedef u64 pte_t; > > > > > > > > typedef signed int s32; > > > > > > > > -/* > > > > +/* > > > > * 3-levels / 4K pages > > > > */ > > > > #define PTRS_PER_PGD_L3_4K (512) > > > > @@ -2823,10 +2823,23 @@ typedef signed int s32; > > > > #define PTRS_PER_PTE_L3_4K (512) > > > > #define PGDIR_SHIFT_L3_4K (30) > > > > #define PGDIR_SIZE_L3_4K ((1UL) << PGDIR_SHIFT_L3_4K) > > > > -#define PGDIR_MASK_L3 4K (~(PGDIR_SIZE_L3_4K-1)) > > > > +#define PGDIR_MASK_L3_4K (~(PGDIR_SIZE_L3_4K-1)) > > > > #define PMD_SHIFT_L3_4K (21) > > > > -#define PMD_SIZE_L3_4K (1UL << PMD_SHIFT_4K) > > > > -#define PMD_MASK_L3 4K (~(PMD_SIZE_4K-1)) > > > > +#define PMD_SIZE_L3_4K (1UL << PMD_SHIFT_L3_4K) > > > > +#define PMD_MASK_L3_4K (~(PMD_SIZE_L3_4K-1)) > > > > + > > > > +/* > > > > + * 3-levels / 64K pages > > > > + */ > > > > +#define PTRS_PER_PGD_L3_64K (64) > > > > +#define PTRS_PER_PMD_L3_64K (8192) > > > > +#define PTRS_PER_PTE_L3_64K (8192) > > > > +#define PGDIR_SHIFT_L3_64K (42) > > > > +#define PGDIR_SIZE_L3_64K ((1UL) << PGDIR_SHIFT_L3_64K) > > > > +#define PGDIR_MASK_L3_64K (~(PGDIR_SIZE_L3_64K-1)) > > > > +#define PMD_SHIFT_L3_64K (29) > > > > +#define PMD_SIZE_L3_64K (1UL << PMD_SHIFT_L3_64K) > > > > +#define PMD_MASK_L3_64K (~(PMD_SIZE_L3_64K-1)) > > > > > > > > /* > > > > * 2-levels / 64K pages > > > > @@ -2868,9 +2881,10 @@ typedef signed int s32; > > > > #define KSYMS_START (0x1) > > > > #define PHYS_OFFSET (0x2) > > > > #define VM_L2_64K (0x4) > > > > -#define VM_L3_4K (0x8) > > > > -#define KDUMP_ENABLED (0x10) > > > > -#define IRQ_STACKS (0x20) > > > > +#define VM_L3_64K (0x8) > > > > +#define VM_L3_4K (0x10) > > > > +#define KDUMP_ENABLED (0x20) > > > > +#define IRQ_STACKS (0x40) > > > > > > > > /* > > > > * sources: Documentation/arm64/memory.txt > > > > -- > > > > 2.1.4 > > > > > > > > -- > > > > Crash-utility mailing list > > > > Crash-utility redhat com > > > > https://www.redhat.com/mailman/listinfo/crash-utility > > > > -- Crash-utility mailing list Crash-utility@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/crash-utility
