Hi Lianbo,
The patch looks good to me, tested OK, so ack.
Thanks,
Tao Liu
On Wed, Jun 5, 2024 at 6:05 PM Lianbo Jiang <lijiang@xxxxxxxxxx> wrote:
>
> Kernel commit 223b5e57d0d5 ("mm/execmem, arch: convert remaining
> overrides of module_alloc to execmem") makes crash session loading
> failure as below:
>
> # ./crash -s
> crash: seek error: kernel virtual address: ffffffff826bb418 type: "page_offset_base"
>
> For X86 64 architecture, currently crash will search for symbol
> "module_load_offset" to determine if the KASLR is enabled, and go
> into the relevant code block. But the symbols "module_load_offset"
> has been removed since Linux v6.10-rc1, which caused the current
> failure.
>
> And this issue can occur with live debugging and core dump file
> debugging.
>
> Let's check the symbol "kaslr_regions" instead of "module_load_offset"
> to fix it.
>
> Signed-off-by: Lianbo Jiang <lijiang@xxxxxxxxxx>
> ---
> symbols.c | 13 ++++++++-----
> 1 file changed, 8 insertions(+), 5 deletions(-)
>
> diff --git a/symbols.c b/symbols.c
> index b7627a83587a..1cdf21d86d69 100644
> --- a/symbols.c
> +++ b/symbols.c
> @@ -619,9 +619,9 @@ strip_symbol_end(const char *name, char *buf)
> * or in /proc/kallsyms on a live system.
> *
> * Setting KASLR_CHECK will trigger a search for "module_load_offset"
> - * during the initial symbol sort operation, and if found, will
> - * set (RELOC_AUTO|KASLR). On live systems, the search is done
> - * here by checking /proc/kallsyms.
> + * or "kaslr_regions" during the initial symbol sort operation, and
> + * if found, will set (RELOC_AUTO|KASLR). On live systems, the search
> + * is done here by checking /proc/kallsyms.
> */
> static void
> kaslr_init(void)
> @@ -646,7 +646,8 @@ kaslr_init(void)
> st->_stext_vmlinux = UNINITIALIZED;
>
> if (ACTIVE() && /* Linux 3.15 */
> - (symbol_value_from_proc_kallsyms("module_load_offset") != BADVAL)) {
> + ((symbol_value_from_proc_kallsyms("kaslr_regions") != BADVAL) ||
> + (symbol_value_from_proc_kallsyms("module_load_offset") != BADVAL))) {
> kt->flags2 |= (RELOC_AUTO|KASLR);
> st->_stext_vmlinux = UNINITIALIZED;
> }
> @@ -14247,7 +14248,9 @@ numeric_forward(const void *P_x, const void *P_y)
> st->_stext_vmlinux = valueof(y);
> }
> if (kt->flags2 & KASLR_CHECK) {
> - if (STREQ(x->name, "module_load_offset") ||
> + if (STREQ(x->name, "kaslr_regions") ||
> + STREQ(y->name, "kaslr_regions") ||
> + STREQ(x->name, "module_load_offset") ||
> STREQ(y->name, "module_load_offset")) {
> kt->flags2 &= ~KASLR_CHECK;
> kt->flags2 |= (RELOC_AUTO|KASLR);
> --
> 2.45.1
> --
> Crash-utility mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxxxxxx
> To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxxxxxx
> https://${domain_name}/admin/lists/devel.lists.crash-utility.osci.io/
> Contribution Guidelines: https://github.com/crash-utility/crash/wiki
--
Crash-utility mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxxxxxx
To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxxxxxx
https://${domain_name}/admin/lists/devel.lists.crash-utility.osci.io/
Contribution Guidelines: https://github.com/crash-utility/crash/wiki
