Hi Baoquan,
> Hi Li Chen,
>
> On 01/20/26 at 08:40pm, Li Chen wrote:
> > kexec_load_purgatory() derives image->start by locating e_entry inside an
> > SHF_EXECINSTR section. If the purgatory object contains multiple executable
> > sections with overlapping sh_addr, the entrypoint check can match more than
> > once and trigger a WARN.
> >
> > Derive the entry section from the purgatory_start symbol when present and
> > compute image->start from its final placement. Keep the existing e_entry
> > fallback for purgatories that do not expose the symbol.
> >
> > WARNING: kernel/kexec_file.c:1009 at kexec_load_purgatory+0x395/0x3c0,
> > CPU#10: kexec/1784
> > Call Trace:
> > <TASK>
> > bzImage64_load+0x133/0xa00
> > __do_sys_kexec_file_load+0x2b3/0x5c0
> > do_syscall_64+0x81/0x610
> > entry_SYSCALL_64_after_hwframe+0x76/0x7e
> >
> > Fixes: 8652d44f466a ("kexec: support purgatories with .text.hot sections")
> > Signed-off-by: Li Chen <[email protected]>
>
> Thanks for fixing the issue. Could you tell how we can trigger this
> issue so that I can reproduce it?
>
> > ---
> > kernel/kexec_file.c | 24 ++++++++++++++++++++++--
> > 1 file changed, 22 insertions(+), 2 deletions(-)
> >
> > diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
> > index 3f1d6c4e8ff2..d3c68c6b4bbc 100644
> > --- a/kernel/kexec_file.c
> > +++ b/kernel/kexec_file.c
> > @@ -880,6 +880,8 @@ static int kexec_calculate_store_digests(struct kimage
> > *image)
> > }
> >
> > #ifdef CONFIG_ARCH_SUPPORTS_KEXEC_PURGATORY
> > +static const Elf_Sym * kexec_purgatory_find_symbol(struct purgatory_info
> > *pi,
> > + const char *name);
>
> Here, is it better to move the whole function body of
> kexec_purgatory_find_symbol() here so that kexec_purgatory_setup_sechdrs()
> can see it too?
>
> Other than the concerns about how to reproducing and above one, this
> patch looks good to me.
Thanks for the review.
For reference, I observed this WARN on x86_64 with linux-next tag
next-20260106 and the savedefconfig included below. Toolchain was GCC
15.2.1 and binutils 2.45.1.
The WARN is triggered in the kexec_file_load path (kexec -s -l), during
purgatory load/relocation. No kexec -e is required.
command I used:
sudo kexec -s -l /boot/vmlinuz-$(uname -r) \
--initrd=/boot/initramfs-$(uname -r).img \
--append="$(cat /proc/cmdline | sed -E \"s/(^| )BOOT_IMAGE=[^ ]+//g\")"
Regarding kexec_purgatory_find_symbol(), agreed; I will move the helper
body above kexec_purgatory_setup_sechdrs() in v2 to avoid the forward
declaration.
kernel config:
https://gist.github.com/FirstLoveLife/b0e7c7da7146f1ba63167b76cb10683a
Regards,
Li
