-----Original Message-----
> >> [PATCH v3] Remove the memory encryption mask to obtain the true physical 
> >> address
> >
> > I forgot to comment on the subject and the commit log..
> > I'll change this to
> >
> >   x86_64: Add support for AMD Secure Memory Encryption
> >
> > On 1/29/2019 9:48 PM, Lianbo Jiang wrote:
> >> For AMD machine with SME feature, if SME is enabled in the first
> >> kernel, the crashed kernel's page table(pgd/pud/pmd/pte) contains
> >> the memory encryption mask, so makedumpfile needs to remove the
> >> memory encryption mask to obtain the true physical address.
> >
> > I added a few official words from some documents:
> > ---
> > On AMD machine with Secure Memory Encryption (SME) feature, if SME is
> > enabled, page tables contain a specific attribute bit (C-bit) in their
> > entries to indicate whether a page is encrypted or unencrypted.
> >
> > So get NUMBER(sme_mask) from vmcoreinfo, which stores the value of
> > the C-bit position, and drop it to obtain the true physical address.
> > ---
> >
> > If these are OK, I'll modify them when merging, so you don't need
> > to repost.
> >
> 
> It's fine to me. Thank you, Kazu.
> 
> Regards,
> Lianbo
> 
> > And, I'm thinking to merge this after the kernel patch gets merged
> > into the mainline.

Hi Lianbo,

I found your patch upstream. Applied to the devel branch.

Thank you!
Kazu


> >
> > Thanks for your work.
> > Kazu
> >
> >>
> >> Signed-off-by: Lianbo Jiang <liji...@redhat.com>
> >> ---
> >> Changes since v1:
> >> 1. Merge them into a patch.
> >> 2. The sme_mask is not an enum number, remove it.
> >> 3. Sanity check whether the sme_mask is in vmcoreinfo.
> >> 4. Deal with the huge pages case.
> >> 5. Cover the 5-level path.
> >>
> >> Changes since v2:
> >> 1. Change the sme_me_mask to entry_mask.
> >> 2. No need to remove the mask when makedumpfile prints out the
> >>    value of the entry.
> >> 3. Remove the sme mask from the pte at the end of the __vtop4_x86_64().
> >> 4. Also need to remove the sme mask from page table entry in
> >>    find_vmemmap_x86_64()
> >>
> >>  arch/x86_64.c  | 30 +++++++++++++++++++-----------
> >>  makedumpfile.c |  4 ++++
> >>  makedumpfile.h |  1 +
> >>  3 files changed, 24 insertions(+), 11 deletions(-)
> >>
> >> diff --git a/arch/x86_64.c b/arch/x86_64.c
> >> index 537fb78..9977466 100644
> >> --- a/arch/x86_64.c
> >> +++ b/arch/x86_64.c
> >> @@ -291,6 +291,7 @@ __vtop4_x86_64(unsigned long vaddr, unsigned long 
> >> pagetable)
> >>    unsigned long page_dir, pgd, pud_paddr, pud_pte, pmd_paddr, pmd_pte;
> >>    unsigned long pte_paddr, pte;
> >>    unsigned long p4d_paddr, p4d_pte;
> >> +  unsigned long entry_mask = ENTRY_MASK;
> >>
> >>    /*
> >>     * Get PGD.
> >> @@ -302,6 +303,9 @@ __vtop4_x86_64(unsigned long vaddr, unsigned long 
> >> pagetable)
> >>                    return NOT_PADDR;
> >>    }
> >>
> >> +  if (NUMBER(sme_mask) != NOT_FOUND_NUMBER)
> >> +          entry_mask &= ~(NUMBER(sme_mask));
> >> +
> >>    if (check_5level_paging()) {
> >>            page_dir += pgd5_index(vaddr) * sizeof(unsigned long);
> >>            if (!readmem(PADDR, page_dir, &pgd, sizeof pgd)) {
> >> @@ -318,7 +322,7 @@ __vtop4_x86_64(unsigned long vaddr, unsigned long 
> >> pagetable)
> >>            /*
> >>             * Get P4D.
> >>             */
> >> -          p4d_paddr  = pgd & ENTRY_MASK;
> >> +          p4d_paddr  = pgd & entry_mask;
> >>            p4d_paddr += p4d_index(vaddr) * sizeof(unsigned long);
> >>            if (!readmem(PADDR, p4d_paddr, &p4d_pte, sizeof p4d_pte)) {
> >>                    ERRMSG("Can't get p4d_pte (p4d_paddr:%lx).\n", 
> >> p4d_paddr);
> >> @@ -331,7 +335,7 @@ __vtop4_x86_64(unsigned long vaddr, unsigned long 
> >> pagetable)
> >>                    ERRMSG("Can't get a valid p4d_pte.\n");
> >>                    return NOT_PADDR;
> >>            }
> >> -          pud_paddr  = p4d_pte & ENTRY_MASK;
> >> +          pud_paddr  = p4d_pte & entry_mask;
> >>    }else {
> >>            page_dir += pgd_index(vaddr) * sizeof(unsigned long);
> >>            if (!readmem(PADDR, page_dir, &pgd, sizeof pgd)) {
> >> @@ -345,7 +349,7 @@ __vtop4_x86_64(unsigned long vaddr, unsigned long 
> >> pagetable)
> >>                    ERRMSG("Can't get a valid pgd.\n");
> >>                    return NOT_PADDR;
> >>            }
> >> -          pud_paddr  = pgd & ENTRY_MASK;
> >> +          pud_paddr  = pgd & entry_mask;
> >>    }
> >>
> >>    /*
> >> @@ -364,13 +368,13 @@ __vtop4_x86_64(unsigned long vaddr, unsigned long 
> >> pagetable)
> >>            return NOT_PADDR;
> >>    }
> >>    if (pud_pte & _PAGE_PSE)        /* 1GB pages */
> >> -          return (pud_pte & ENTRY_MASK & PUD_MASK) +
> >> +          return (pud_pte & entry_mask & PUD_MASK) +
> >>                    (vaddr & ~PUD_MASK);
> >>
> >>    /*
> >>     * Get PMD.
> >>     */
> >> -  pmd_paddr  = pud_pte & ENTRY_MASK;
> >> +  pmd_paddr  = pud_pte & entry_mask;
> >>    pmd_paddr += pmd_index(vaddr) * sizeof(unsigned long);
> >>    if (!readmem(PADDR, pmd_paddr, &pmd_pte, sizeof pmd_pte)) {
> >>            ERRMSG("Can't get pmd_pte (pmd_paddr:%lx).\n", pmd_paddr);
> >> @@ -384,13 +388,13 @@ __vtop4_x86_64(unsigned long vaddr, unsigned long 
> >> pagetable)
> >>            return NOT_PADDR;
> >>    }
> >>    if (pmd_pte & _PAGE_PSE)        /* 2MB pages */
> >> -          return (pmd_pte & ENTRY_MASK & PMD_MASK) +
> >> +          return (pmd_pte & entry_mask & PMD_MASK) +
> >>                    (vaddr & ~PMD_MASK);
> >>
> >>    /*
> >>     * Get PTE.
> >>     */
> >> -  pte_paddr  = pmd_pte & ENTRY_MASK;
> >> +  pte_paddr  = pmd_pte & entry_mask;
> >>    pte_paddr += pte_index(vaddr) * sizeof(unsigned long);
> >>    if (!readmem(PADDR, pte_paddr, &pte, sizeof pte)) {
> >>            ERRMSG("Can't get pte (pte_paddr:%lx).\n", pte_paddr);
> >> @@ -403,7 +407,7 @@ __vtop4_x86_64(unsigned long vaddr, unsigned long 
> >> pagetable)
> >>            ERRMSG("Can't get a valid pte.\n");
> >>            return NOT_PADDR;
> >>    }
> >> -  return (pte & ENTRY_MASK) + PAGEOFFSET(vaddr);
> >> +  return (pte & entry_mask) + PAGEOFFSET(vaddr);
> >>  }
> >>
> >>  unsigned long long
> >> @@ -636,6 +640,7 @@ find_vmemmap_x86_64()
> >>    unsigned long pmd, tpfn;
> >>    unsigned long pvaddr = 0;
> >>    unsigned long data_addr = 0, last_data_addr = 0, start_data_addr = 0;
> >> +  unsigned long pmask = PMASK;
> >>    /*
> >>     * data_addr is the paddr of the page holding the page structs.
> >>     * We keep lists of contiguous pages and the pfn's that their
> >> @@ -656,6 +661,9 @@ find_vmemmap_x86_64()
> >>            return FAILED;
> >>    }
> >>
> >> +  if (NUMBER(sme_mask) != NOT_FOUND_NUMBER)
> >> +          pmask &= ~(NUMBER(sme_mask));
> >> +
> >>    pagestructsize = size_table.page;
> >>    hugepagesize = PTRS_PER_PMD * info->page_size;
> >>    vaddr_base = info->vmemmap_start;
> >> @@ -686,7 +694,7 @@ find_vmemmap_x86_64()
> >>            }
> >>
> >>            /* mask the pgd entry for the address of the pud page */
> >> -          pud_addr &= PMASK;
> >> +          pud_addr &= pmask;
> >>            if (pud_addr == 0)
> >>                      continue;
> >>            /* read the entire pud page */
> >> @@ -699,7 +707,7 @@ find_vmemmap_x86_64()
> >>            /* pudp points to an entry in the pud page */
> >>            for (pudp = (unsigned long *)pud_page, pudindex = 0;
> >>                                    pudindex < PTRS_PER_PUD; pudindex++, 
> >> pudp++) {
> >> -                  pmd_addr = *pudp & PMASK;
> >> +                  pmd_addr = *pudp & pmask;
> >>                    /* read the entire pmd page */
> >>                    if (pmd_addr == 0)
> >>                            continue;
> >> @@ -741,7 +749,7 @@ find_vmemmap_x86_64()
> >>                             * - we discontiguous page is a string of valids
> >>                             */
> >>                            if (pmd) {
> >> -                                  data_addr = (pmd & PMASK);
> >> +                                  data_addr = (pmd & pmask);
> >>                                    if (start_range) {
> >>                                            /* first-time kludge */
> >>                                            start_data_addr = data_addr;
> >> diff --git a/makedumpfile.c b/makedumpfile.c
> >> index 8923538..2237eb8 100644
> >> --- a/makedumpfile.c
> >> +++ b/makedumpfile.c
> >> @@ -977,6 +977,8 @@ next_page:
> >>    read_size = MIN(info->page_size - PAGEOFFSET(paddr), size);
> >>
> >>    pgaddr = PAGEBASE(paddr);
> >> +  if (NUMBER(sme_mask) != NOT_FOUND_NUMBER)
> >> +          pgaddr = pgaddr & ~(NUMBER(sme_mask));
> >>    pgbuf = cache_search(pgaddr, read_size);
> >>    if (!pgbuf) {
> >>            ++cache_miss;
> >> @@ -2276,6 +2278,7 @@ write_vmcoreinfo_data(void)
> >>    WRITE_NUMBER("NR_FREE_PAGES", NR_FREE_PAGES);
> >>    WRITE_NUMBER("N_ONLINE", N_ONLINE);
> >>    WRITE_NUMBER("pgtable_l5_enabled", pgtable_l5_enabled);
> >> +  WRITE_NUMBER("sme_mask", sme_mask);
> >>
> >>    WRITE_NUMBER("PG_lru", PG_lru);
> >>    WRITE_NUMBER("PG_private", PG_private);
> >> @@ -2672,6 +2675,7 @@ read_vmcoreinfo(void)
> >>    READ_NUMBER("NR_FREE_PAGES", NR_FREE_PAGES);
> >>    READ_NUMBER("N_ONLINE", N_ONLINE);
> >>    READ_NUMBER("pgtable_l5_enabled", pgtable_l5_enabled);
> >> +  READ_NUMBER("sme_mask", sme_mask);
> >>
> >>    READ_NUMBER("PG_lru", PG_lru);
> >>    READ_NUMBER("PG_private", PG_private);
> >> diff --git a/makedumpfile.h b/makedumpfile.h
> >> index 73813ed..e97b2e7 100644
> >> --- a/makedumpfile.h
> >> +++ b/makedumpfile.h
> >> @@ -1912,6 +1912,7 @@ struct number_table {
> >>    long    NR_FREE_PAGES;
> >>    long    N_ONLINE;
> >>    long    pgtable_l5_enabled;
> >> +  long    sme_mask;
> >>
> >>    /*
> >>    * Page flags
> >> --
> >> 2.17.1
> >>
> >
> >



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