On 2023/03/29 21:44, Daisuke Hatayama (Fujitsu) wrote:
> makedumpfile fails as follows for memory dumps collected by sadump
> when 5-level paging is enabled on the corresponding systems:
>
> # makedumpfile -l -d 31 -x ./vmlinux ./dump.sadump dump.sadump-ld31
> __vtop4_x86_64: Can't get a valid pgd.
> ...snip...
> __vtop4_x86_64: Can't get a valid pgd.
> calc_kaslr_offset: failed to calculate kaslr_offset and phys_base; default to 0
> __vtop4_x86_64: Can't get a valid pgd.
> readmem: Can't convert a virtual address(ffffffff82fce960) to physical address.
> readmem: type_addr: 0, addr:ffffffff82fce960, size:1024
> cpu_online_mask_init: Can't read cpu_online_mask memory.
>
> makedumpfile Failed.
>
> This is because 5-level paging support has not been done yet for
> sadump; the work of the 5-level paging support was done by the commit
> 30a3214a7193e94c551c0cebda5918a72a35c589 (PATCH 4/4 arch/x86_64: Add
> 5-level paging support) but that was focused on the core part only.
>
> Having said that, most of things has already been finished in the
> commit. What needs to be newly added for sadump is just how to check
> if 5-level paging is enabled for a given memory dump.
>
> For that purpose, let's refer to CR4.LA57, bit 12 of CR4, representing
> whether 5-level paging is enabled or not. We can do this because
> memory dumps collected by sadump have SMRAM as note information and
> they include CR4 together with the other control registers.
>
> Signed-off-by: HATAYAMA Daisuke <d.hatayama@xxxxxxxxxxx>
> ---
> sadump_info.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/sadump_info.c b/sadump_info.c
> index adfa8dc..2c44068 100644
> --- a/sadump_info.c
> +++ b/sadump_info.c
> @@ -1362,6 +1362,7 @@ static int linux_banner_sanity_check(ulong cr3)
> #define PTI_USER_PGTABLE_BIT (info->page_shift)
> #define PTI_USER_PGTABLE_MASK (1 << PTI_USER_PGTABLE_BIT)
> #define CR3_PCID_MASK 0xFFFull
> +#define CR4_LA57 (1 << 12)
> int
> calc_kaslr_offset(void)
> {
> @@ -1397,6 +1398,8 @@ calc_kaslr_offset(void)
> else
> cr3 = smram.Cr3 & ~CR3_PCID_MASK;
>
> + NUMBER(pgtable_l5_enabled) = !!(smram.Cr4 & CR4_LA57);
> +
> /* Convert virtual address of IDT table to physical address */
> idtr_paddr = vtop4_x86_64_pagetable(idtr, cr3);
> if (idtr_paddr == NOT_PADDR) {
> @@ -1417,6 +1420,7 @@ calc_kaslr_offset(void)
>
> DEBUG_MSG("sadump: idtr=%" PRIx64 "\n", idtr);
> DEBUG_MSG("sadump: cr3=%" PRIx64 "\n", cr3);
> + DEBUG_MSG("sadump: cr4=%" PRIx32 "\n", smram.Cr4);
> DEBUG_MSG("sadump: idtr(phys)=%" PRIx64 "\n", idtr_paddr);
> DEBUG_MSG("sadump: devide_error(vmlinux)=%lx\n",
> divide_error_vmlinux);
Thanks, applied.
https://github.com/makedumpfile/makedumpfile/commit/58553ad03187f0cf208d6c4a0dc026c6338e5edd
(oh, "devide" is there..)
Thanks,
Kazu
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