Re: [PATCH v3 02/11] x86/kexec: Add extra pointers to transition page table PGD, PUD, PMD and PTE

H. Peter Anvin
2012-12-27T03:34:21Z

Hmm... this code is being redone at the moment... this might conflict.

Daniel Kiper <daniel.kiper@oracle.com> wrote:

>Some implementations (e.g. Xen PVOPS) could not use part of identity
>page table
>to construct transition page table. It means that they require separate
>PUDs,
>PMDs and PTEs for virtual and physical (identity) mapping. To satisfy
>that
>requirement add extra pointer to PGD, PUD, PMD and PTE and align
>existing code.
>
>Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
>---
> arch/x86/include/asm/kexec.h | 10 +++++++---
> arch/x86/kernel/machine_kexec_64.c | 12 ++++++------
> 2 files changed, 13 insertions(+), 9 deletions(-)
>
>diff --git a/arch/x86/include/asm/kexec.h
>b/arch/x86/include/asm/kexec.h
>index 6080d26..cedd204 100644
>--- a/arch/x86/include/asm/kexec.h
>+++ b/arch/x86/include/asm/kexec.h
>@@ -157,9 +157,13 @@ struct kimage_arch {
> };
> #else
> struct kimage_arch {
>- pud_t *pud;
>- pmd_t *pmd;
>- pte_t *pte;
>+ pgd_t *pgd;
>+ pud_t *pud0;
>+ pud_t *pud1;
>+ pmd_t *pmd0;
>+ pmd_t *pmd1;
>+ pte_t *pte0;
>+ pte_t *pte1;
> };
> #endif
>
>diff --git a/arch/x86/kernel/machine_kexec_64.c
>b/arch/x86/kernel/machine_kexec_64.c
>index b3ea9db..976e54b 100644
>--- a/arch/x86/kernel/machine_kexec_64.c
>+++ b/arch/x86/kernel/machine_kexec_64.c
>@@ -137,9 +137,9 @@ out:
>
> static void free_transition_pgtable(struct kimage *image)
> {
>- free_page((unsigned long)image->arch.pud);
>- free_page((unsigned long)image->arch.pmd);
>- free_page((unsigned long)image->arch.pte);
>+ free_page((unsigned long)image->arch.pud0);
>+ free_page((unsigned long)image->arch.pmd0);
>+ free_page((unsigned long)image->arch.pte0);
> }
>
> static int init_transition_pgtable(struct kimage *image, pgd_t *pgd)
>@@ -157,7 +157,7 @@ static int init_transition_pgtable(struct kimage
>*image, pgd_t *pgd)
> pud = (pud_t *)get_zeroed_page(GFP_KERNEL);
> if (!pud)
> goto err;
>- image->arch.pud = pud;
>+ image->arch.pud0 = pud;
> set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE));
> }
> pud = pud_offset(pgd, vaddr);
>@@ -165,7 +165,7 @@ static int init_transition_pgtable(struct kimage
>*image, pgd_t *pgd)
> pmd = (pmd_t *)get_zeroed_page(GFP_KERNEL);
> if (!pmd)
> goto err;
>- image->arch.pmd = pmd;
>+ image->arch.pmd0 = pmd;
> set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
> }
> pmd = pmd_offset(pud, vaddr);
>@@ -173,7 +173,7 @@ static int init_transition_pgtable(struct kimage
>*image, pgd_t *pgd)
> pte = (pte_t *)get_zeroed_page(GFP_KERNEL);
> if (!pte)
> goto err;
>- image->arch.pte = pte;
>+ image->arch.pte0 = pte;
> set_pmd(pmd, __pmd(__pa(pte) | _KERNPG_TABLE));
> }
> pte = pte_offset_kernel(pmd, vaddr);

--
Sent from my mobile phone. Please excuse brevity and lack of formatting.