On Thu, Aug 15, 2024 at 11:56 AM Kuan-Ying Lee <kuan-ying.lee(a)canonical.com>
wrote:
On Tue, Aug 13, 2024 at 12:04:30PM +0800, lijiang wrote:
> Thank you for the patch, Kuan-Ying.
>
> On Thu, Aug 8, 2024 at 9:09 PM <
devel-request(a)lists.crash-utility.osci.io>
> wrote:
>
> > Date: Thu, 8 Aug 2024 13:35:41 +0800
> > From: Kuan-Ying Lee <kuan-ying.lee(a)canonical.com>
> > Subject: [Crash-utility] [PATCH 1/3] arm64: Introduction of support
> > for 16K page with 2-level table support
> > To: kuan-ying.lee(a)canonical.com,
> > devel(a)lists.crash-utility.osci.io
> > Message-ID: <20240808053543.10910-2-kuan-ying.lee(a)canonical.com>
> >
> > Introduction of ARM64 support for 16K page size with 2-level page
> > table and 36 VA bits.
> >
> > Signed-off-by: Kuan-Ying Lee <kuan-ying.lee(a)canonical.com>
> > ---
> > arm64.c | 90 +++++++++++++++++++++++++++++++++++++++++++++++++++++++--
> > defs.h | 11 +++++++
> > 2 files changed, 98 insertions(+), 3 deletions(-)
> >
> > diff --git a/arm64.c b/arm64.c
> > index 8ed1aaf919d6..002cc0078dad 100644
> > --- a/arm64.c
> > +++ b/arm64.c
> > @@ -42,6 +42,7 @@ 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_2level_16k(ulong, ulong, physaddr_t *, int);
> > static int arm64_vtop_3level_16k(ulong, ulong, physaddr_t *, int);
> > static int arm64_vtop_3level_4k(ulong, ulong, physaddr_t *, int);
> > static int arm64_vtop_4level_4k(ulong, ulong, physaddr_t *, int);
> > @@ -426,7 +427,16 @@ arm64_init(int when)
> > (char *)malloc(PTRS_PER_PTE_L3_16K
*
> > 8)) == NULL)
> > error(FATAL, "cannot malloc
ptbl
> > space.");
> > } else {
> > - error(FATAL, "we only support 47 bits,
3
> > level for 16K page now.");
> >
>
> I copied it from kernel code here:
>
> config PGTABLE_LEVELS
> int
> default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
> default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
> default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 ||
> ARM64_VA_BITS_52)
> default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
> default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
> default 4 if ARM64_16K_PAGES && (ARM64_VA_BITS_48 ||
> ARM64_VA_BITS_52)
> default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
> default 5 if ARM64_4K_PAGES && ARM64_VA_BITS_52
>
> Crash tools do not support 16K pages with 4-level tables and 48 or 52 VA
> bits, is it possible to add a similar check for this one? I'm not sure if
> you have any plans to support it.
Yes, it's on my to-do list. I will find time to implement it later.
Thank you for working on it, Kuan-Ying.
I have a request: Can you help add a check in the current patch and say
that crash tools do not support 48(or 52)bits, 4-level page tables for 16K
pages?
For example:
...
error(FATAL, "Only support [47 bits, 3-level] or [36 bits, 2-level] for 16K
page now.");
...
or
error(FATAL, "Do not support 48 bits or 52 bits, 4-level for 16K page
now.");
Thanks
Lianbo
Thank you.
>
> BTW: It also has the same issue in the [PATCH 3/3].
>
> + machdep->flags |= VM_L2_16K;
> > + if (!machdep->ptrs_per_pgd)
> > + machdep->ptrs_per_pgd =
> > PTRS_PER_PGD_L2_16K;
> > + if ((machdep->pgd =
> > + (char
*)malloc(machdep->ptrs_per_pgd *
> > 8)) == NULL)
> > + error(FATAL, "cannot malloc pgd
> > space.");
> > + if ((machdep->ptbl =
> > + (char *)malloc(PTRS_PER_PTE_L2_16K
*
> > 8)) == NULL)
> > + error(FATAL, "cannot malloc
ptbl
> > space.");
> > + machdep->pmd = NULL; /* not used */
> > }
> > machdep->pud = NULL; /* not used */
> > break;
> > @@ -1064,6 +1074,8 @@ arm64_dump_machdep_table(ulong arg)
> > fprintf(fp, "%sVM_L2_64K", others++ ? "|" :
"");
> > if (machdep->flags & VM_L3_64K)
> > fprintf(fp, "%sVM_L3_64K", others++ ? "|" :
"");
> > + if (machdep->flags & VM_L2_16K)
> > + fprintf(fp, "%sVM_L2_16K", others++ ? "|" :
"");
> > if (machdep->flags & VM_L3_16K)
> > fprintf(fp, "%sVM_L3_16K", others++ ? "|" :
"");
> > if (machdep->flags & VM_L3_4K)
> > @@ -1113,6 +1125,8 @@ arm64_dump_machdep_table(ulong arg)
> > "arm64_vtop_3level_4k" :
> > machdep->flags & VM_L4_4K ?
> > "arm64_vtop_4level_4k" :
> > + machdep->flags & VM_L2_16K ?
> > + "arm64_vtop_2level_16k" :
> > machdep->flags & VM_L3_16K ?
> > "arm64_vtop_3level_16k" :
> > machdep->flags & VM_L3_64K ?
> > @@ -1122,6 +1136,8 @@ arm64_dump_machdep_table(ulong arg)
> > "arm64_vtop_3level_4k" :
> > machdep->flags & VM_L4_4K ?
> > "arm64_vtop_4level_4k" :
> > + machdep->flags & VM_L2_16K ?
> > + "arm64_vtop_2level_16k" :
> > machdep->flags & VM_L3_16K ?
> > "arm64_vtop_3level_16k" :
> > machdep->flags & VM_L3_64K ?
> > @@ -1814,7 +1830,7 @@ 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_64K|VM_L3_4K|VM_L4_4K|VM_L3_16K))
> > + switch (machdep->flags &
> > (VM_L2_64K|VM_L3_64K|VM_L3_4K|VM_L4_4K|VM_L2_16K|VM_L3_16K))
> > {
> > case VM_L2_64K:
> > return arm64_vtop_2level_64k(kernel_pgd, kvaddr, paddr,
> > verbose);
> > @@ -1824,6 +1840,8 @@ arm64_kvtop(struct task_context *tc, ulong
kvaddr,
> > physaddr_t *paddr, int verbos
> > return arm64_vtop_3level_4k(kernel_pgd, kvaddr, paddr,
> > verbose);
> > case VM_L4_4K:
> > return arm64_vtop_4level_4k(kernel_pgd, kvaddr, paddr,
> > verbose);
> > + case VM_L2_16K:
> > + return arm64_vtop_2level_16k(kernel_pgd, kvaddr, paddr,
> > verbose);
> > case VM_L3_16K:
> > return arm64_vtop_3level_16k(kernel_pgd, kvaddr, paddr,
> > verbose);
> > default:
> > @@ -1841,7 +1859,7 @@ arm64_uvtop(struct task_context *tc, ulong
uvaddr,
> > physaddr_t *paddr, int verbos
> >
> > *paddr = 0;
> >
> > - switch (machdep->flags &
> > (VM_L2_64K|VM_L3_64K|VM_L3_4K|VM_L4_4K|VM_L3_16K))
> > + switch (machdep->flags &
> > (VM_L2_64K|VM_L3_64K|VM_L3_4K|VM_L4_4K|VM_L2_16K|VM_L3_16K))
> > {
> > case VM_L2_64K:
> > return arm64_vtop_2level_64k(user_pgd, uvaddr, paddr,
> > verbose);
> > @@ -1851,6 +1869,8 @@ arm64_uvtop(struct task_context *tc, ulong
uvaddr,
> > physaddr_t *paddr, int verbos
> > return arm64_vtop_3level_4k(user_pgd, uvaddr, paddr,
> > verbose);
> > case VM_L4_4K:
> > return arm64_vtop_4level_4k(user_pgd, uvaddr, paddr,
> > verbose);
> > + case VM_L2_16K:
> > + return arm64_vtop_2level_16k(user_pgd, uvaddr, paddr,
> > verbose);
> > case VM_L3_16K:
> > return arm64_vtop_3level_16k(user_pgd, uvaddr, paddr,
> > verbose);
> > default:
> > @@ -2012,6 +2032,70 @@ no_page:
> > return FALSE;
> > }
> >
> > +static int
> > +arm64_vtop_2level_16k(ulong pgd, ulong vaddr, physaddr_t *paddr, int
> > verbose)
> > +{
> > + ulong *pgd_base, *pgd_ptr, pgd_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, machdep->ptrs_per_pgd *
sizeof(ulong));
> > + pgd_ptr = pgd_base + (((vaddr) >> PGDIR_SHIFT_L2_16K) &
> > (machdep->ptrs_per_pgd - 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
> > + * #define __PAGETABLE_PMD_FOLDED
> > + */
> > +
> > + if ((pgd_val & PMD_TYPE_MASK) == PMD_TYPE_SECT) {
> > + ulong sectionbase = (pgd_val & SECTION_PAGE_MASK_32MB)
&
> > PHYS_MASK;
> > + if (verbose) {
> > + fprintf(fp, " PAGE: %lx (32MB%s)\n\n",
> > sectionbase,
> > + IS_ZEROPAGE(sectionbase) ? ", ZERO
PAGE" :
> > "");
> > + arm64_translate_pte(pgd_val, 0, 0);
> > + }
> > + *paddr = sectionbase + (vaddr &
~SECTION_PAGE_MASK_32MB);
> > + return TRUE;
> > + }
> > +
> > + pte_base = (ulong *)PTOV(pgd_val & PHYS_MASK &
> > (s32)machdep->pagemask);
> > + FILL_PTBL(pte_base, KVADDR, PTRS_PER_PTE_L2_16K *
sizeof(ulong));
> > + pte_ptr = pte_base + (((vaddr) >> machdep->pageshift) &
> > (PTRS_PER_PTE_L2_16K - 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 %s\n\n",
> > PAGEBASE(*paddr),
> > + IS_ZEROPAGE(PAGEBASE(*paddr)) ? "(ZERO
> > PAGE)" : "");
> > + 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;
> > +}
> >
>
> The above code seems to have an indentation issue, other changes are fine
> to me.
>
> Thanks
> Lianbo
>
>
> > static int
> > arm64_vtop_3level_16k(ulong pgd, ulong vaddr, physaddr_t *paddr, int
> > verbose)
> > {
> > diff --git a/defs.h b/defs.h
> > index 1b7649d9f05c..dfbd2419f969 100644
> > --- a/defs.h
> > +++ b/defs.h
> > @@ -3302,6 +3302,16 @@ typedef signed int s32;
> > #define PGDIR_MASK_48VA (~(PGDIR_SIZE_48VA - 1))
> > #define PGDIR_OFFSET_48VA(X) (((ulong)(X)) & (PGDIR_SIZE_48VA - 1))
> >
> > +/*
> > + * 2-levels / 16K pages
> > + * 36-bit VA
> > + */
> > +#define PTRS_PER_PGD_L2_16K (2048)
> > +#define PTRS_PER_PTE_L2_16K (2048)
> > +#define PGDIR_SHIFT_L2_16K (25)
> > +#define PGDIR_SIZE_L2_16K ((1UL) << PGDIR_SHIFT_L2_16K)
> > +#define PGDIR_MASK_L2_16K (~(PGDIR_SIZE_L2_16K-1))
> > +
> > /*
> > * 3-levels / 16K pages
> > * 47-bit VA
> > @@ -3383,6 +3393,7 @@ typedef signed int s32;
> > #define OVERFLOW_STACKS (0x1000)
> > #define ARM64_MTE (0x2000)
> > #define VM_L3_16K (0x4000)
> > +#define VM_L2_16K (0x8000)
> >
> > /*
> > * Get kimage_voffset from /dev/crash
> > --
> > 2.34.1
> >