All of lore.kernel.org
 help / color / mirror / Atom feed
From: Nikos Tsironis <ntsironis@arrikto.com>
To: mpatocka@redhat.com, tglx@linutronix.de,
	linux-rt-users@vger.kernel.org, msnitzer@redhat.com,
	dm-devel@redhat.com, linux-kernel@vger.kernel.org
Cc: swood@redhat.com, linux-fsdevel@vger.kernel.org, dwagner@suse.de,
	bigeasy@linutronix.de, iliastsi@arrikto.com,
	ntsironis@arrikto.com
Subject: [PATCH RT 2/2 v4] list_bl: avoid BUG when the list is not locked
Date: Wed, 13 Nov 2019 15:10:42 +0200	[thread overview]
Message-ID: <20191113131042.7719-1-ntsironis@arrikto.com> (raw)
In-Reply-To: <alpine.LRH.2.02.1911121110430.12815@file01.intranet.prod.int.rdu2.redhat.com>

list_bl would crash with BUG() if we used it without locking.
dm-snapshot uses its own locking on realtime kernels (it can't use
list_bl because list_bl uses raw spinlock and dm-snapshot takes other
non-raw spinlocks while holding bl_lock).

To avoid this BUG we deactivate the list debug checks for list_bl on
realtime kernels.

This patch is intended only for the realtime kernel patchset, not for
the upstream kernel.

Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
---
 include/linux/list_bl.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/list_bl.h b/include/linux/list_bl.h
index da38433240f5..3585b2f6b948 100644
--- a/include/linux/list_bl.h
+++ b/include/linux/list_bl.h
@@ -25,7 +25,7 @@
 #define LIST_BL_LOCKMASK	0UL
 #endif
 
-#ifdef CONFIG_DEBUG_LIST
+#if defined(CONFIG_DEBUG_LIST) && !defined(CONFIG_PREEMPT_RT_BASE)
 #define LIST_BL_BUG_ON(x) BUG_ON(x)
 #else
 #define LIST_BL_BUG_ON(x)
-- 
2.11.0


      parent reply	other threads:[~2019-11-13 13:11 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-11-12 16:16 [PATCH RT 2/2 v2] list_bl: avoid BUG when the list is not locked Mikulas Patocka
2019-11-13 10:29 ` Nikos Tsironis
2019-11-13 11:16   ` Mikulas Patocka
2019-11-13 11:50     ` Nikos Tsironis
2019-11-13 12:05       ` Mikulas Patocka
2019-11-13 11:18 ` [PATCH RT 2/2 v3] " Mikulas Patocka
2019-11-13 13:10 ` Nikos Tsironis [this message]

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=20191113131042.7719-1-ntsironis@arrikto.com \
    --to=ntsironis@arrikto.com \
    --cc=bigeasy@linutronix.de \
    --cc=dm-devel@redhat.com \
    --cc=dwagner@suse.de \
    --cc=iliastsi@arrikto.com \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-rt-users@vger.kernel.org \
    --cc=mpatocka@redhat.com \
    --cc=msnitzer@redhat.com \
    --cc=swood@redhat.com \
    --cc=tglx@linutronix.de \
    /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.