About Segmentation fault of mkfs.erofs in AOSP

[Gao Xiang]

On Tue, Dec 01, 2020 at 07:48:43PM +0800, Yue Hu wrote:
> On Tue, 1 Dec 2020 19:42:53 +0800
> Gao Xiang <hsiangkao at redhat.com> wrote:
> 
> > Hi Yue,
> > 
> > On Tue, Dec 01, 2020 at 07:23:09PM +0800, Yue Hu wrote:
> > > hi guys,
> > > 
> > > I'm trying using erofs for super.img(dynamic partition) under Android 10. But i have met an issue below when building images:
> > > 
> > > ```log
> > > EROFS: write_uncompressed_block() Line[140] Writing 3517 uncompressed data to block 63950
> > > EROFS: erofs_mkfs_build_tree() Line[1011] add file /tmp/merge_target_files_jnIVhM/output/VENDOR/etc/xtwifi.conf (nid 8185600, type 1)
> > > EROFS: erofs_mkfs_build_tree() Line[1011] add file /tmp/merge_target_files_jnIVhM/output/VENDOR/etc (nid 1790208, type 2)
> > > out/host/linux-x86/bin/mkerofsimage.sh: line 79: 188014 Segmentation fault      (core dumped) $MAKE_EROFS_CMD
> > > ```
> > > 
> > > Have you met this kind of issue? I'm trying to debug the problem, looks like memory related.
> > > 
> > > BTW: i'm using latest erofs-utils in AOSP master branch (https://android.googlesource.com/platform/external/erofs-utils/).  
> > 
> > Which lz4 version is used? it would be better to use lz4 1.9.3
> > (or 1.9.2 with some unexpected CR issues.)
> 
> Hi Xiang,
> 
> ok, let me check.

At least, lz4 1.8.3 ~ 1.9.1 are buggy, for more details, see:
https://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs-utils.git/tree/README?h=dev#n107

> 
> > For more details, please see README.
> > 
> > If the expected lz4 version is used, could you kindly leave gdb
> > backtrace message here as well? 
> 
> Trying to get the bt for the case.

Yeah, bt will fall into lz4 internal functions if the lz4
version is too low.

Thanks,
Gao Xiang

> 
> Thx.
> 
> > 
> > Thanks,
> > Gao Xiang
> > 
> > > 
> > > Thx.
> > >   
> > 
>