Re: kexec reboot failed due to commit 75d090fd167ac

From: Kirill A. Shutemov
Date: Thu Sep 21 2023 - 15:53:40 EST


On Thu, Sep 21, 2023 at 11:54:15AM +0200, Linux regression tracking (Thorsten Leemhuis) wrote:
> On 13.09.23 16:24, Kirill A. Shutemov wrote:
> > On Mon, Sep 11, 2023 at 05:57:07PM +0300, Kirill A. Shutemov wrote:
> >> On Mon, Sep 11, 2023 at 10:56:36PM +0800, Dave Young wrote:
> >>>> early console in extract_kernel
> >>>> input_data: 0x000000807eb433a8
> >>>> input_len: 0x0000000000d26271
> >>>> output: 0x000000807b000000
> >>>> output_len: 0x0000000004800c10
> >>>> kernel_total_size: 0x0000000003e28000
> >>>> needed_size: 0x0000000004a00000
> >>>> trampoline_32bit: 0x000000000009d000
> >>>>
> >>>> Decompressing Linux... out of pgt_buf in arch/x86/boot/compressed/ident_map_64.c!?
> >>>> pages->pgt_buf_offset: 0x0000000000006000
> >>>> pages->pgt_buf_size: 0x0000000000006000
> >>>>
> >>>> Error: kernel_ident_mapping_init() failed
> > [...]
> >> The problem is not limited to unaccepted memory, it also triggers if we
> >> reach efi_get_rsdp_addr() in the same setup.
> >>
> >> I think we have several problems here.
> > [...]
> >> Any comments?
> >
> > I struggle to come up with anything better than increasing the constant to
> > a value that "ought to be enough for anybody" ©, let's say 128K.
> >
> > And we can eliminate logic on no-KASLR vs. KASLR vs. KASLR+VERBOSE_BOOTUP.
> >
> > Objections?
>
> Apparently not, as there was no reply since then (which is why I show up
> here, as it looked like fixing this regression stalled).

It has been fixed in upstream by the commit f530ee95b72e
("x86/boot/compressed: Reserve more memory for page tables")

--
Kiryl Shutsemau / Kirill A. Shutemov