Indoh-san, > -----Original Message----- > From: Takao Indoh [mailto:indou.takao@xxxxxxxxxxxxxx] > Sent: Tuesday, October 10, 2017 6:26 PM > To: crash-utility@xxxxxxxxxx; Hatayama, Daisuke/畑山 大輔 > <d.hatayama@xxxxxxxxxxxxxx> > Subject: [PATCH 1/3] Introduce x86_64_kvtop_pagetable > > This patch introduces new function x86_64_kvtop_pagetable() to translate > virtual address to physical address. Unlike x86_64_kvtop(), > x86_64_kvtop_pagetable() simply converts given virtual address to > physical address using pagetable. > > To solve kaslr problem of virsh dump and sadump, kaslr offset and > phys_base need to be calculated before symbol data is loaded. This > calculation needs translation of kernel virtual address to physical > address. Current kvtop() implementation tries to use x86_64_VTOP for > translation at first, but this does not work for this purpose because > x86_64_VTOP uses phys_base. So x86_64_kvtop_pagetable() is needed which > does not use phys_base. > Thanks for the patch set. I don't have comment on this patch. It looks good to me. > Signed-off-by: Takao Indoh <indou.takao@xxxxxxxxxxxxxx> > --- > defs.h | 1 + > x86_64.c | 26 +++++++++++++++++++++++++- > 2 files changed, 26 insertions(+), 1 deletion(-) > > diff --git a/defs.h b/defs.h > index fd97ffe..cddca93 100644 > --- a/defs.h > +++ b/defs.h > @@ -5622,6 +5622,7 @@ void x86_64_display_idt_table(void); > #define display_idt_table() x86_64_display_idt_table() > long x86_64_exception_frame(ulong, ulong, char *, struct bt_info *, FILE *); > #define EFRAME_INIT (0) > +int x86_64_kvtop_pagetable(ulong, physaddr_t *, int); > > struct x86_64_pt_regs_offsets { > long r15; > diff --git a/x86_64.c b/x86_64.c > index 44d0c98..fc48425 100644 > --- a/x86_64.c > +++ b/x86_64.c > @@ -119,6 +119,7 @@ static int x86_64_verify_paddr(uint64_t); > static void GART_init(void); > static void x86_64_exception_stacks_init(void); > static int in_START_KERNEL_map(ulong); > +static int __x86_64_kvtop(struct task_context *, ulong, physaddr_t *, int, > int); > > struct machine_specific x86_64_machine_specific = { 0 }; > > @@ -1964,6 +1965,17 @@ no_upage: > return FALSE; > } > > +int > +x86_64_kvtop_pagetable(ulong kvaddr, physaddr_t *paddr, int verbose) > +{ > + return __x86_64_kvtop(NULL, kvaddr, paddr, verbose, 1); > +} > + > +static int > +x86_64_kvtop(struct task_context *tc, ulong kvaddr, physaddr_t *paddr, int > verbose) > +{ > + return __x86_64_kvtop(tc, kvaddr, paddr, verbose, 0); > +} > > /* > * Translates a kernel virtual address to its physical address. cmd_vtop() > @@ -1971,7 +1983,7 @@ no_upage: > * other callers quietly accept the translation. > */ > static int > -x86_64_kvtop(struct task_context *tc, ulong kvaddr, physaddr_t *paddr, int > verbose) > +__x86_64_kvtop(struct task_context *tc, ulong kvaddr, physaddr_t *paddr, int > verbose, int use_pagetable) > { > ulong *pml4; > ulong *pgd; > @@ -1985,6 +1997,16 @@ x86_64_kvtop(struct task_context *tc, ulong kvaddr, > physaddr_t *paddr, int verbo > ulong pte; > physaddr_t physpage; > > + if (use_pagetable) { > + FILL_PML4(); > + pml4 = ((ulong *)machdep->machspec->pml4) + > pml4_index(kvaddr); > + if (verbose) { > + fprintf(fp, "PML4 DIRECTORY: %lx\n", > vt->kernel_pgd[0]); > + fprintf(fp, "PAGE DIRECTORY: %lx\n", *pml4); > + } > + goto start_vtop_with_pagetable; > + } > + > if (!IS_KVADDR(kvaddr)) > return FALSE; > > @@ -2031,6 +2053,8 @@ x86_64_kvtop(struct task_context *tc, ulong kvaddr, > physaddr_t *paddr, int verbo > fprintf(fp, "PAGE DIRECTORY: %lx\n", *pml4); > } > } > + > +start_vtop_with_pagetable: > if (!(*pml4) & _PAGE_PRESENT) > goto no_kpage; > pgd_paddr = (*pml4) & PHYSICAL_PAGE_MASK; > -- > 2.9.5 -- Crash-utility mailing list Crash-utility@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/crash-utility
