[Crash-utility] [PATH v4 2/2] arm64: add 4-level translation

AKASHI Takahiro takahiro.akashi at linaro.org
Wed Jun 1 01:56:05 UTC 2016


On Tue, May 31, 2016 at 03:30:44PM -0400, Dave Anderson wrote:
> 
> This patch looks good -- if it wasn't layered on top of the KASLR patch,
> I would check it into github.

This patch is almost independent from KASLR support, except that
adding new flags, VM_L4_4K and NEW_VMEMMAP, is conflicting.

When you merge it, please make a change.

-Takahiro AKASHI

> Thanks,
>   Dave
> 
> 
> ----- Original Message -----
> > From: AKASHI Takahiro <akax.hiro at gmail.com>
> > 
> > Signed-off-by: AKASHI Takahiro <takahiro.akashi at linaro.org>
> > ---
> >  arm64.c | 120
> >  ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++----
> >  defs.h  |  25 +++++++++++++-
> >  2 files changed, 137 insertions(+), 8 deletions(-)
> > 
> > diff --git a/arm64.c b/arm64.c
> > index c16ea67..b6bfbf3 100644
> > --- a/arm64.c
> > +++ b/arm64.c
> > @@ -36,6 +36,7 @@ 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 int arm64_vtop_4level_4k(ulong, ulong, physaddr_t *, int);
> >  static ulong arm64_get_task_pgd(ulong);
> >  static void arm64_irq_stack_init(void);
> >  static void arm64_stackframe_init(void);
> > @@ -233,18 +234,26 @@ arm64_init(int when)
> >  		switch (machdep->pagesize)
> >  		{
> >  		case 4096:
> > -			machdep->flags |= VM_L3_4K;
> >  			machdep->ptrs_per_pgd = PTRS_PER_PGD_L3_4K;
> >  			if ((machdep->pgd =
> >  			    (char *)malloc(PTRS_PER_PGD_L3_4K * 8)) == NULL)
> >  				error(FATAL, "cannot malloc pgd space.");
> > +			if (machdep->machspec->VA_BITS > PGDIR_SHIFT_L4_4K) {
> > +				machdep->flags |= VM_L4_4K;
> > +				if ((machdep->pud =
> > +				    (char *)malloc(PTRS_PER_PUD_L4_4K * 8))
> > +				    == NULL)
> > +					error(FATAL, "cannot malloc pud space.");
> > +			} else {
> > +				machdep->flags |= VM_L3_4K;
> > +				machdep->pud = NULL;  /* not used */
> > +			}
> >  			if ((machdep->pmd =
> >  			    (char *)malloc(PTRS_PER_PMD_L3_4K * 8)) == NULL)
> >  				error(FATAL, "cannot malloc pmd space.");
> >  			if ((machdep->ptbl =
> >  			    (char *)malloc(PTRS_PER_PTE_L3_4K * 8)) == NULL)
> >  				error(FATAL, "cannot malloc ptbl space.");
> > -			machdep->pud = NULL;  /* not used */
> >  			break;
> >  
> >  		case 65536:
> > @@ -282,8 +291,8 @@ arm64_init(int when)
> >  				error(FATAL, "cannot determine page size\n");
> >  		}
> >  
> > -		machdep->last_pud_read = 0;  /* not used */
> >  		machdep->last_pgd_read = 0;
> > +		machdep->last_pud_read = 0;
> >  		machdep->last_pmd_read = 0;
> >  		machdep->last_ptbl_read = 0;
> >  		machdep->clear_machdep_cache = arm64_clear_machdep_cache;
> > @@ -462,6 +471,8 @@ arm64_dump_machdep_table(ulong arg)
> >  		fprintf(fp, "%sVM_L3_64K", others++ ? "|" : "");
> >  	if (machdep->flags & VM_L3_4K)
> >  		fprintf(fp, "%sVM_L3_4K", others++ ? "|" : "");
> > +	if (machdep->flags & VM_L4_4K)
> > +		fprintf(fp, "%sVM_L4_4K", others++ ? "|" : "");
> >  	if (machdep->flags & VMEMMAP)
> >  		fprintf(fp, "%sVMEMMAP", others++ ? "|" : "");
> >  	if (machdep->flags & KDUMP_ENABLED)
> > @@ -494,11 +505,15 @@ arm64_dump_machdep_table(ulong arg)
> >  	fprintf(fp, "               uvtop: arm64_uvtop()->%s()\n",
> >  		machdep->flags & VM_L3_4K ?
> >  		"arm64_vtop_3level_4k" :
> > +		machdep->flags & VM_L4_4K ?
> > +		"arm64_vtop_4level_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" :
> > +		machdep->flags & VM_L4_4K ?
> > +		"arm64_vtop_4level_4k" :
> >  		machdep->flags & VM_L3_64K ?
> >  		"arm64_vtop_3level_64k" : "arm64_vtop_2level_64k");
> >  	fprintf(fp, "        get_task_pgd: arm64_get_task_pgd()\n");
> > @@ -531,8 +546,13 @@ arm64_dump_machdep_table(ulong arg)
> >          fprintf(fp, "  xendump_panic_task: (n/a)\n");
> >          fprintf(fp, "    get_xendump_regs: (n/a)\n");
> >  	fprintf(fp, "   line_number_hooks: (not used)\n");
> > -	fprintf(fp, "       last_pud_read: (not used)\n");
> >  	fprintf(fp, "       last_pgd_read: %lx\n", machdep->last_pgd_read);
> > +	fprintf(fp, "       last_pud_read: ");
> > +	if ((PAGESIZE() == 65536) ||
> > +	    ((PAGESIZE() == 4096) && !(machdep->flags & VM_L4_4K)))
> > +		fprintf(fp, "(not used)\n");
> > +	else
> > +		fprintf(fp, "%lx\n", machdep->last_pud_read);
> >  	fprintf(fp, "       last_pmd_read: ");
> >  	if (PAGESIZE() == 65536)
> >  		fprintf(fp, "(not used)\n");
> > @@ -541,6 +561,7 @@ arm64_dump_machdep_table(ulong arg)
> >  	fprintf(fp, "      last_ptbl_read: %lx\n", machdep->last_ptbl_read);
> >  	fprintf(fp, " clear_machdep_cache: arm64_clear_machdep_cache()\n");
> >  	fprintf(fp, "                 pgd: %lx\n", (ulong)machdep->pgd);
> > +	fprintf(fp, "                 pud: %lx\n", (ulong)machdep->pud);
> >  	fprintf(fp, "                 pmd: %lx\n", (ulong)machdep->pmd);
> >  	fprintf(fp, "                ptbl: %lx\n", (ulong)machdep->ptbl);
> >  	fprintf(fp, "        ptrs_per_pgd: %d\n", machdep->ptrs_per_pgd);
> > @@ -843,7 +864,7 @@ 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))
> > +	switch (machdep->flags & (VM_L2_64K|VM_L3_64K|VM_L3_4K|VM_L4_4K))
> >  	{
> >  	case VM_L2_64K:
> >  		return arm64_vtop_2level_64k(kernel_pgd, kvaddr, paddr, verbose);
> > @@ -851,6 +872,8 @@ arm64_kvtop(struct task_context *tc, ulong kvaddr,
> > physaddr_t *paddr, int verbos
> >  		return arm64_vtop_3level_64k(kernel_pgd, kvaddr, paddr, verbose);
> >  	case VM_L3_4K:
> >  		return arm64_vtop_3level_4k(kernel_pgd, kvaddr, paddr, verbose);
> > +	case VM_L4_4K:
> > +		return arm64_vtop_4level_4k(kernel_pgd, kvaddr, paddr, verbose);
> >  	default:
> >  		return FALSE;
> >  	}
> > @@ -866,7 +889,7 @@ 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))
> > +	switch (machdep->flags & (VM_L2_64K|VM_L3_64K|VM_L3_4K|VM_L4_4K))
> >  	{
> >  	case VM_L2_64K:
> >  		return arm64_vtop_2level_64k(user_pgd, uvaddr, paddr, verbose);
> > @@ -874,6 +897,8 @@ arm64_uvtop(struct task_context *tc, ulong uvaddr,
> > physaddr_t *paddr, int verbos
> >  		return arm64_vtop_3level_64k(user_pgd, uvaddr, paddr, verbose);
> >  	case VM_L3_4K:
> >  		return arm64_vtop_3level_4k(user_pgd, uvaddr, paddr, verbose);
> > +	case VM_L4_4K:
> > +		return arm64_vtop_4level_4k(user_pgd, uvaddr, paddr, verbose);
> >  	default:
> >  		return FALSE;
> >  	}
> > @@ -1092,6 +1117,85 @@ no_page:
> >  	return FALSE;
> >  }
> >  
> > +static int
> > +arm64_vtop_4level_4k(ulong pgd, ulong vaddr, physaddr_t *paddr, int verbose)
> > +{
> > +	ulong *pgd_base, *pgd_ptr, pgd_val;
> > +	ulong *pud_base, *pud_ptr, pud_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_L4_4K * sizeof(ulong));
> > +	pgd_ptr = pgd_base + (((vaddr) >> PGDIR_SHIFT_L4_4K) & (PTRS_PER_PGD_L4_4K
> > - 1));
> > +        pgd_val = ULONG(machdep->pgd + PGDIR_OFFSET(pgd_ptr));
> > +        if (verbose)
> > +                fprintf(fp, "   PGD: %lx => %lx\n", (ulong)pgd_ptr,
> > pgd_val);
> > +	if (!pgd_val)
> > +		goto no_page;
> > +
> > +	pud_base = (ulong *)PTOV(pgd_val & PHYS_MASK & PGDIR_MASK);
> > +
> > +	FILL_PUD(pud_base, KVADDR, PTRS_PER_PUD_L4_4K * sizeof(ulong));
> > +	pud_ptr = pud_base + (((vaddr) >> PUD_SHIFT_L4_4K) & (PTRS_PER_PUD_L4_4K -
> > 1));
> > +        pud_val = ULONG(machdep->pud + PAGEOFFSET(pud_ptr));
> > +        if (verbose)
> > +                fprintf(fp, "   PUD: %lx => %lx\n", (ulong)pud_ptr,
> > pud_val);
> > +	if (!pud_val)
> > +		goto no_page;
> > +
> > +	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));
> > +        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_2MB) & PHYS_MASK;
> > +		if (verbose) {
> > +			fprintf(fp, "  PAGE: %lx  (2MB)\n\n", sectionbase);
> > +			arm64_translate_pte(pmd_val, 0, 0);
> > +		}
> > +		*paddr = sectionbase + (vaddr & ~SECTION_PAGE_MASK_2MB);
> > +		return TRUE;
> > +	}
> > +
> > +	pte_base = (ulong *)PTOV(pmd_val & PHYS_MASK & (s32)machdep->pagemask);
> > +	FILL_PTBL(pte_base, KVADDR, PTRS_PER_PTE_L4_4K * sizeof(ulong));
> > +	pte_ptr = pte_base + (((vaddr) >> machdep->pageshift) & (PTRS_PER_PTE_L4_4K
> > - 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 ulong
> >  arm64_get_task_pgd(ulong task)
> >  {
> > @@ -2556,7 +2660,7 @@ arm64_calc_virtual_memory_ranges(void)
> >  
> >  	STRUCT_SIZE_INIT(page, "page");
> >  
> > -        switch (machdep->flags & (VM_L2_64K|VM_L3_64K|VM_L3_4K))
> > +        switch (machdep->flags & (VM_L2_64K|VM_L3_64K|VM_L3_4K|VM_L4_4K))
> >          {
> >          case VM_L2_64K:
> >          case VM_L3_64K:
> > @@ -2564,6 +2668,8 @@ arm64_calc_virtual_memory_ranges(void)
> >  		break;
> >          case VM_L3_4K:
> >  		PUD_SIZE = PGDIR_SIZE_L3_4K;
> > +        case VM_L4_4K:
> > +		PUD_SIZE = PUD_SIZE_L4_4K;
> >  		break;
> >          }
> >  
> > diff --git a/defs.h b/defs.h
> > index 406a865..17a4fbd 100644
> > --- a/defs.h
> > +++ b/defs.h
> > @@ -1054,7 +1054,7 @@ extern struct machdep_table *machdep;
> >              readmem((ulonglong)((ulong)(PGD)), TYPE, machdep->pgd,
> >              \
> >                      SIZE, "pgd page", FAULT_ON_ERROR);
> >                      \
> >              machdep->last_pgd_read = (ulong)(PGD);
> >              \
> > -    }
> > +    }
> >  
> >  #define FILL_PUD(PUD, TYPE, SIZE) 					    \
> >      if (!IS_LAST_PUD_READ(PUD)) {
> >      \
> > @@ -2884,6 +2884,28 @@ typedef signed int s32;
> >  #define PMD_MASK_L3_4K       (~(PMD_SIZE_L3_4K-1))
> >  
> >  /*
> > + * 4-levels / 4K pages
> > + * 48-bit VA
> > + */
> > +#define PTRS_PER_PGD_L4_4K   ((1UL) << (48 - 39))
> > +#define PTRS_PER_PUD_L4_4K   (512)
> > +#define PTRS_PER_PMD_L4_4K   (512)
> > +#define PTRS_PER_PTE_L4_4K   (512)
> > +#define PGDIR_SHIFT_L4_4K    (39)
> > +#define PGDIR_SIZE_L4_4K     ((1UL) << PGDIR_SHIFT_L4_4K)
> > +#define PGDIR_MASK_L4_4K     (~(PGDIR_SIZE_L4_4K-1))
> > +#define PUD_SHIFT_L4_4K      (30)
> > +#define PUD_SIZE_L4_4K       ((1UL) << PUD_SHIFT_L4_4K)
> > +#define PUD_MASK_L4_4K       (~(PUD_SIZE_L4_4K-1))
> > +#define PMD_SHIFT_L4_4K      (21)
> > +#define PMD_SIZE_L4_4K       (1UL << PMD_SHIFT_L4_4K)
> > +#define PMD_MASK_L4_4K       (~(PMD_SIZE_L4_4K-1))
> > +
> > +#define PGDIR_SIZE      (1UL << ((48 - 39) + 3))
> > +#define PGDIR_MASK      (~(PGDIR_SIZE - 1))
> > +#define PGDIR_OFFSET(X) (((ulong)(X)) & (PGDIR_SIZE - 1))
> > +
> > +/*
> >   * 3-levels / 64K pages
> >   */
> >  #define PTRS_PER_PGD_L3_64K  (64)
> > @@ -2941,6 +2963,7 @@ typedef signed int s32;
> >  #define KDUMP_ENABLED (0x20)
> >  #define IRQ_STACKS    (0x40)
> >  #define NEW_VMEMMAP   (0x80)
> > +#define VM_L4_4K      (0x100)
> >  
> >  /*
> >   * sources: Documentation/arm64/memory.txt
> > --
> > 2.8.1
> > 
> > --
> > Crash-utility mailing list
> > Crash-utility at redhat.com
> > https://www.redhat.com/mailman/listinfo/crash-utility
> > 
> 
> --
> Crash-utility mailing list
> Crash-utility at redhat.com
> https://www.redhat.com/mailman/listinfo/crash-utility

-- 
Thanks,
-Takahiro AKASHI




More information about the Crash-utility mailing list