Re: Kernel bug: "general protection fault in bch2_btree_path_traverse_one"

[Matthew Wilcox]

On Fri, Dec 20, 2024 at 07:43:44PM +0800, Haichi Wang wrote:
> Dear Linux maintainers and reviewers:
> We are reporting a Linux kernel bug titled **general protection fault in bch2_btree_path_traverse_one**, discovered using a modified version of Syzkaller.

No, you aren't.  This is a terrible bug report, and you seem to have
sent several with the same defects.  First, read:

https://blog.regehr.org/archives/2037

Then, specifically to reporting a kernel bug *LOOK AT HOW OTHER PEOPLE
DO IT*.  Your email includes lots of stuff that is of no help and
doesn't include the most important thing -- the kernel logs from around
the time of the failure.

> ### Affected Files
> The affected files, as obtained from the VM log, are listed below. The corresponding maintainers were identified using `./scripts/get_maintainer.pl`:
> fs/bcachefs/btree_update_interior.c
> fs/bcachefs/alloc_foreground.c
> fs/bcachefs/btree_iter.c
> fs/bcachefs/btree_trans_commit.c
> fs/namespace.c
> arch/x86/entry/common.c
> fs/bcachefs/recovery.c
> fs/bcachefs/recovery_passes.c
> fs/bcachefs/super.c
> fs/bcachefs/fs.c
> fs/super.c

This is useless.

> ### Kernel Versions
> - **Kernel Version Tested:** v6.12-rc6:59b723cd2adbac2a34fc8e12c74ae26ae45bf230
> - **Latest Kernel Version Reproduced On:** f44d154d6e3d633d4c49a5d6a8aed0e4684ae25e

Useful

> ### Environment Details
> - **QEMU Version:** QEMU emulator version 4.2.1 (Debian 1:4.2-3ubuntu6.29)  
> - **GCC Version:** gcc (Ubuntu 11.4.0-2ubuntu1~20.04) 11.4.0  
> - **Syzkaller Version:** 2b3ef1577cde5da4fd1f7ece079731e140351177

Useful

> ### Attached Files
> We have attached the following files to assist in reproducing and diagnosing the bug:
> - **Bug Title:** `bugtitle`  
> - **Bug Report:** `report`  
> - **Machine Information:** `machineInfo`  
> - **Kernel Config:** `config`  
> - **Compiled Kernel Image:** `vmlinux`  

You didn't attach these things, but please don't.

We want the stacktrace.  Preferably passed through
scripts/decode_stacktrace.sh so we get nice symbols.