linux-modules.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Sedat Dilek <sedat.dilek@gmail.com>
To: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Masahiro Yamada <masahiroy@kernel.org>,
	"linux-kbuild@vger.kernel.org" <linux-kbuild@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Nathan Chancellor <nathan@kernel.org>,
	Nick Desaulniers <ndesaulniers@google.com>,
	Nicolas Schier <nicolas@fjasle.eu>,
	Peter Zijlstra <peterz@infradead.org>,
	"linux-modules@vger.kernel.org" <linux-modules@vger.kernel.org>,
	"llvm@lists.linux.dev" <llvm@lists.linux.dev>,
	Ard Biesheuvel <ardb@kernel.org>,
	Sami Tolvanen <samitolvanen@google.com>,
	"linuxppc-dev@lists.ozlabs.org" <linuxppc-dev@lists.ozlabs.org>,
	"Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Subject: Re: Build/boot problem with 7b4537199a4a (Re: [PATCH v6 02/10] kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS)
Date: Sat, 20 Aug 2022 14:05:43 +0200	[thread overview]
Message-ID: <CA+icZUU1R6vmmKussGBXGBzR8We2b5mAnfWT5BCcfvYY3vk+Zw@mail.gmail.com> (raw)
In-Reply-To: <38605f6a-a568-f884-f06f-ea4da5b214f0@csgroup.eu>

On Sat, Aug 20, 2022 at 12:04 PM Christophe Leroy
<christophe.leroy@csgroup.eu> wrote:
>
> Hi,
>
> Le 13/05/2022 à 13:39, Masahiro Yamada a écrit :
> > include/{linux,asm-generic}/export.h defines a weak symbol, __crc_*
> > as a placeholder.
> >
> > Genksyms writes the version CRCs into the linker script, which will be
> > used for filling the __crc_* symbols. The linker script format depends
> > on CONFIG_MODULE_REL_CRCS. If it is enabled, __crc_* holds the offset
> > to the reference of CRC.
> >
> > It is time to get rid of this complexity.
> >
> > Now that modpost parses text files (.*.cmd) to collect all the CRCs,
> > it can generate C code that will be linked to the vmlinux or modules.
> >
> > Generate a new C file, .vmlinux.export.c, which contains the CRCs of
> > symbols exported by vmlinux. It is compiled and linked to vmlinux in
> > scripts/link-vmlinux.sh.
> >
> > Put the CRCs of symbols exported by modules into the existing *.mod.c
> > files. No additional build step is needed for modules. As before,
> > *.mod.c are compiled and linked to *.ko in scripts/Makefile.modfinal.
> >
> > No linker magic is used here. The new C implementation works in the
> > same way, whether CONFIG_RELOCATABLE is enabled or not.
> > CONFIG_MODULE_REL_CRCS is no longer needed.
> >
> > Previously, Kbuild invoked additional $(LD) to update the CRCs in
> > objects, but this step is unneeded too.
> >
> > Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
> > Tested-by: Nathan Chancellor <nathan@kernel.org>
> > Tested-by: Nicolas Schier <nicolas@fjasle.eu>
> > Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
>
> Problem with v6.0-rc1
> Problem with v5.19
> No problem with v5.18
>
> Bisected to 7b4537199a4a ("kbuild: link symbol CRCs at final link,
> removing CONFIG_MODULE_REL_CRCS")
>

What you are looking for is...

commit 7d13fd96df875a9d786ee6dcc8fec460d35d4b12
("modpost: fix module versioning when a symbol lacks valid CRC")

It's pending in kbuild.git#fixes.

-Sedat-

[1] https://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild.git/commit/?h=fixes&id=7d13fd96df875a9d786ee6dcc8fec460d35d4b12
[2] https://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild.git/log/?h=fixes

> The above patch leads to the following problem building
> mpc85xx_defconfig + CONFIG_RELOCATABLE
>
>    LD      vmlinux
>    SYSMAP  System.map
>    SORTTAB vmlinux
>    CHKREL  vmlinux
> WARNING: 451 bad relocations
> c0b0f26d R_PPC_UADDR32     .head.text-0x3ff9f2bc
> c0b0f271 R_PPC_UADDR32     .head.text-0x3ffac300
> c0b0f275 R_PPC_UADDR32     .head.text-0x3ffb0bdc
> c0b0f279 R_PPC_UADDR32     .head.text-0x3fe1e080
> c0b0f27d R_PPC_UADDR32     .head.text-0x3fe1df4c
> c0b0f281 R_PPC_UADDR32     .head.text-0x3fe21514
> c0b0f285 R_PPC_UADDR32     .head.text-0x3fe211c0
> c0b0f289 R_PPC_UADDR32     .head.text-0x3ffabda0
> c0b0f28d R_PPC_UADDR32     .head.text-0x3fe21258
> c0b0f291 R_PPC_UADDR32     .head.text-0x3fe074d0
> c0b0f295 R_PPC_UADDR32     .head.text-0x3fe07ad4
> c0b0f299 R_PPC_UADDR32     .head.text-0x3fe13470
> c0b0f29d R_PPC_UADDR32     .head.text-0x3fe22700
> c0b0f2a1 R_PPC_UADDR32     .head.text-0x3ff4b8e0
> c0b0f2a5 R_PPC_UADDR32     .head.text-0x3fe08320
> c0b0f2a9 R_PPC_UADDR32     .head.text-0x3fe220dc
> c0b0f2ad R_PPC_UADDR32     .head.text-0x3fe21da0
> c0b0f2b1 R_PPC_UADDR32     .head.text-0x3ff89dc0
> c0b0f2b5 R_PPC_UADDR32     .head.text-0x3fe16524
> c0b0f2b9 R_PPC_UADDR32     .head.text-0x3fe1ef74
> c0b0f2bd R_PPC_UADDR32     .head.text-0x3ff98b84
> c0b0f2c1 R_PPC_UADDR32     .head.text-0x3fdef9a0
> c0b0f2c5 R_PPC_UADDR32     .head.text-0x3fdf21ac
> c0b0f2c9 R_PPC_UADDR32     .head.text-0x3ff993c4
> ...
> c0b0f969 R_PPC_UADDR32     .head.text-0x3ff89dc0
> c0b0f96d R_PPC_UADDR32     .head.text-0x3fe9ad40
> c0b0f971 R_PPC_UADDR32     .head.text-0x3ff2eb00
> c0b0f975 R_PPC_UADDR32     .head.text-0x3ff89dc0
>
> And boot fails:
>
> Run /init as init process
> kernel tried to execute user page (0) - exploit attempt? (uid: 0)
> BUG: Unable to handle kernel instruction fetch (NULL pointer?)
> Faulting instruction address: 0x00000000
> Oops: Kernel access of bad area, sig: 11 [#1]
> BE PAGE_SIZE=4K MPC8544 DS
> Modules linked in:
> CPU: 0 PID: 1 Comm: init Not tainted 5.18.0-rc1-00054-g7b4537199a4a #1523
> NIP:  00000000 LR: c00150e4 CTR: 00000000
> REGS: c3091e10 TRAP: 0400   Not tainted  (5.18.0-rc1-00054-g7b4537199a4a)
> MSR:  00009000 <EE,ME>  CR: 88000422  XER: 20000000
>
> GPR00: 00004000 c3091f00 c30c8000 00000000 00000013 b7bb9f4c b7bd8f60
> bfee6650
> GPR08: 00000054 00000000 c0b0f26d 00000000 c13b0000 00000000 bfee6668
> 00000000
> GPR16: 84e08000 00000000 08000000 00000064 00000000 00102000 00000001
> 00000001
> GPR24: 00000001 00000001 b7b9c7d0 10000034 00000009 b7bd8f38 b7bd9854
> b7bd8688
> NIP [00000000] 0x0
> LR [c00150e4] ret_from_syscall+0x0/0x28
> Call Trace:
> [c3091f00] [c0000af0] InstructionStorage+0x150/0x160 (unreliable)
> --- interrupt: c00 at 0xb7bb28e8
> NIP:  b7bb28e8 LR: b7bb1384 CTR: b7bb1218
> REGS: c3091f10 TRAP: 0c00   Not tainted  (5.18.0-rc1-00054-g7b4537199a4a)
> MSR:  0002d000 <CE,EE,PR,ME>  CR: 28000422  XER: 20000000
>
> GPR00: 0000002d bfee61f0 00000000 00000000 00000013 b7bb9f4c b7bd8f60
> bfee6650
> GPR08: 00000054 00000020 bfee6648 00000000 00000001 00000000 bfee6668
> 00000000
> GPR16: 84e08000 00000000 08000000 00000064 00000000 00102000 00000001
> 00000001
> GPR24: 00000001 00000001 b7b9c7d0 10000034 00000009 b7bd8f38 b7bd9854
> b7bd8688
> NIP [b7bb28e8] 0xb7bb28e8
> LR [b7bb1384] 0xb7bb1384
> --- interrupt: c00
> Instruction dump:
> XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
> XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
> ---[ end trace 0000000000000000 ]---
>
> Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
>
>
>
> Christophe

  reply	other threads:[~2022-08-20 12:06 UTC|newest]

Thread overview: 39+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-05-13 11:39 [PATCH v6 00/10] kbuild: yet another series of cleanups (modpost, LTO, MODULE_REL_CRCS, export.h) Masahiro Yamada
2022-05-13 11:39 ` [PATCH v6 01/10] modpost: extract symbol versions from *.cmd files Masahiro Yamada
2022-05-28 22:47   ` Guenter Roeck
2022-05-29  4:27     ` Masahiro Yamada
2022-05-13 11:39 ` [PATCH v6 02/10] kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS Masahiro Yamada
2022-08-20 10:02   ` Build/boot problem with 7b4537199a4a (Re: [PATCH v6 02/10] kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS) Christophe Leroy
2022-08-20 12:05     ` Sedat Dilek [this message]
2022-08-20 14:10       ` Christophe Leroy
2022-08-20 12:51     ` Masahiro Yamada
2022-08-20 14:15       ` Christophe Leroy
2022-08-20 17:01         ` Masahiro Yamada
2022-08-20 17:51           ` Christophe Leroy
2022-05-13 11:39 ` [PATCH v6 03/10] kbuild: stop merging *.symversions Masahiro Yamada
2022-05-13 11:39 ` [PATCH v6 04/10] genksyms: adjust the output format to modpost Masahiro Yamada
2022-05-13 11:39 ` [PATCH v6 05/10] kbuild: do not create *.prelink.o for Clang LTO or IBT Masahiro Yamada
2022-05-13 11:39 ` [PATCH v6 06/10] kbuild: check static EXPORT_SYMBOL* by script instead of modpost Masahiro Yamada
2022-05-25  8:31   ` Guenter Roeck
2022-05-25 10:51     ` Masahiro Yamada
2022-06-07 14:22   ` Jon Hunter
2022-06-07 14:25     ` Nathan Chancellor
2022-06-07 14:34       ` Jon Hunter
2022-05-13 11:39 ` [PATCH v6 07/10] kbuild: make built-in.a rule robust against too long argument error Masahiro Yamada
2022-05-13 11:39 ` [PATCH v6 08/10] kbuild: make *.mod " Masahiro Yamada
2022-05-13 11:39 ` [PATCH v6 09/10] kbuild: add cmd_and_savecmd macro Masahiro Yamada
2022-05-13 11:39 ` [PATCH v6 10/10] kbuild: rebuild multi-object modules when objtool is updated Masahiro Yamada
2022-05-13 12:20 ` [PATCH v6 00/10] kbuild: yet another series of cleanups (modpost, LTO, MODULE_REL_CRCS, export.h) Masahiro Yamada
     [not found]   ` <CA+icZUUWww3fXvjQcefgFuq=tPO6+FYDbHE2E5PmL-BSJg4+cw@mail.gmail.com>
2022-05-22  6:49     ` Masahiro Yamada
2022-05-22  9:45       ` Sedat Dilek
2022-05-22 14:15         ` Sedat Dilek
2022-05-22 16:09           ` Masahiro Yamada
2022-05-22 16:18             ` Sedat Dilek
2022-05-22 22:34               ` Sedat Dilek
     [not found]   ` <2c496d24174e63b27ec047f383df6700@matoro.tk>
2022-08-06  7:23     ` Sedat Dilek
2022-08-06 13:12       ` matoro
2022-08-08  5:54     ` Masahiro Yamada
2022-08-08 13:26       ` matoro
2022-08-08 17:36         ` Masahiro Yamada
2022-08-08 18:42           ` matoro
2022-08-09 15:20             ` Masahiro Yamada

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=CA+icZUU1R6vmmKussGBXGBzR8We2b5mAnfWT5BCcfvYY3vk+Zw@mail.gmail.com \
    --to=sedat.dilek@gmail.com \
    --cc=ardb@kernel.org \
    --cc=christophe.leroy@csgroup.eu \
    --cc=kirill.shutemov@linux.intel.com \
    --cc=linux-kbuild@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-modules@vger.kernel.org \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=llvm@lists.linux.dev \
    --cc=masahiroy@kernel.org \
    --cc=nathan@kernel.org \
    --cc=ndesaulniers@google.com \
    --cc=nicolas@fjasle.eu \
    --cc=peterz@infradead.org \
    --cc=samitolvanen@google.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).