All of lore.kernel.org
 help / color / mirror / Atom feed
From: 胡玮文 <sehuww@mail.scut.edu.cn>
To: linux-erofs@lists.ozlabs.org
Subject: fuse returns ENOENT to openat() for symlink probabilistically
Date: Thu, 21 Jan 2021 18:12:33 +0800	[thread overview]
Message-ID: <20210121101233.GC6680@DESKTOP-N4CECTO.huww98.cn> (raw)

Hi all,

I'm working on setting up CI service to run tests automatically. Now I have got
tests with kernel mount succeeded. But some tests with fuse fails
probabilistically. Here are my discoveries:

* if I run fssum in tests/src from experimental-tests branch multiple times, it
returns different checksums for the same image and same erofsfuse process.

* if I run "diff -r" on the source and the mounted directories, all file
content matches. but sometimes, diff reports "diff:
test-mount/lib/.libs/liberofs.la: No such file or directory". This file is a
symlink to "../liberofs.la". Then I use strace to confirm that openat() system
call to this path returned ENOENT incorrectly. strace outputs:

openat(AT_FDCWD, "test-mount/lib/.libs/liberofs.la", O_RDONLY) = -1 ENOENT (No such file or directory)

* However, If I just do "cat test-mount/lib/.libs/liberofs.la" several hundreds
of times, I cannot trigger this issue.

* I can reproduce this on both compressed and uncompressed images.

There seems a race condition, but I cannot figure it out. I'm not familiar with
fuse. But I would like to debug further if someone can provide me any advice or
guidance.

Thanks,
Hu Weiwen


             reply	other threads:[~2021-01-21 10:14 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-01-21 10:12 胡玮文 [this message]
2021-01-21 11:27 ` fuse returns ENOENT to openat() for symlink probabilistically Gao Xiang
2021-01-21 16:31   ` [PATCH] erofs-utils: fuse: fix random readlink error Hu Weiwen
2021-01-22  0:34     ` Gao Xiang
2021-01-22  1:00       ` 胡玮文
2021-01-22  1:49         ` Gao Xiang
2021-01-23 13:18           ` 胡玮文
2021-01-23 15:22             ` Gao Xiang
2021-01-23 15:36               ` Gao Xiang
2021-01-29 18:07               ` [PATCH v2] " Hu Weiwen
2021-02-09 19:38                 ` Gao Xiang via Linux-erofs
2021-02-13 14:36                   ` [PATCH v3] " 胡玮文
2021-02-28 13:30                   ` [PATCH v2] " Li GuiFu via Linux-erofs
2021-02-28 13:53                   ` [PATCH v4] " Gao Xiang via Linux-erofs

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=20210121101233.GC6680@DESKTOP-N4CECTO.huww98.cn \
    --to=sehuww@mail.scut.edu.cn \
    --cc=linux-erofs@lists.ozlabs.org \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.