From: tip-bot for Michael Kelley <tipbot@zytor.com>
To: linux-tip-commits@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, mikelley@microsoft.com,
gregkh@linuxfoundation.org, hpa@zytor.com, mingo@kernel.org,
tglx@linutronix.de
Subject: [tip:irq/urgent] genirq: Properly pair kobject_del() with kobject_add()
Date: Mon, 19 Aug 2019 07:01:06 -0700 [thread overview]
Message-ID: <tip-e1ee29624746fbf667f80e8ae3815a76e4d1bd5b@git.kernel.org> (raw)
In-Reply-To: <1564703564-4116-1-git-send-email-mikelley@microsoft.com>
Commit-ID: e1ee29624746fbf667f80e8ae3815a76e4d1bd5b
Gitweb: https://git.kernel.org/tip/e1ee29624746fbf667f80e8ae3815a76e4d1bd5b
Author: Michael Kelley <mikelley@microsoft.com>
AuthorDate: Thu, 1 Aug 2019 23:53:53 +0000
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitDate: Mon, 19 Aug 2019 15:56:28 +0200
genirq: Properly pair kobject_del() with kobject_add()
If alloc_descs() fails before irq_sysfs_init() has run, free_desc() in the
cleanup path will call kobject_del() even though the kobject has not been
added with kobject_add().
Fix this by making the call to kobject_del() conditional on whether
irq_sysfs_init() has run.
This problem surfaced because commit aa30f47cf666 ("kobject: Add support
for default attribute groups to kobj_type") makes kobject_del() stricter
about pairing with kobject_add(). If the pairing is incorrrect, a WARNING
and backtrace occur in sysfs_remove_group() because there is no parent.
[ tglx: Add a comment to the code ]
Fixes: ecb3f394c5db ("genirq: Expose interrupt information through sysfs")
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1564703564-4116-1-git-send-email-mikelley@microsoft.com
---
kernel/irq/irqdesc.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 9484e88dabc2..51f42f3caf09 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -437,8 +437,14 @@ static void free_desc(unsigned int irq)
*
* The sysfs entry must be serialized against a concurrent
* irq_sysfs_init() as well.
+ *
+ * If irq_sysfs_init() has not yet been invoked (early boot), then
+ * irq_kobj_base is NULL and the descriptor was never added.
+ * kobject_del() complains about a object with no parent, so make
+ * it conditional.
*/
- kobject_del(&desc->kobj);
+ if (irq_kobj_base)
+ kobject_del(&desc->kobj);
delete_irq_desc(irq);
/*
next prev parent reply other threads:[~2019-08-19 14:01 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1564703564-4116-1-git-send-email-mikelley@microsoft.com>
2019-08-02 6:34 ` [PATCH 1/1] genirq: Properly pair kobject_del with kobject_add gregkh
[not found] ` <MWHPR21MB078463AB854A336842118405D7D90@MWHPR21MB0784.namprd21.prod.outlook.com>
2019-08-03 7:15 ` gregkh
2019-08-03 7:43 ` Thomas Gleixner
2019-08-19 14:01 ` tip-bot for Michael Kelley [this message]
[not found] ` <20190819212758.6D03D22CEC@mail.kernel.org>
2019-08-19 21:58 ` [tip:irq/urgent] genirq: Properly pair kobject_del() with kobject_add() Michael Kelley
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=tip-e1ee29624746fbf667f80e8ae3815a76e4d1bd5b@git.kernel.org \
--to=tipbot@zytor.com \
--cc=gregkh@linuxfoundation.org \
--cc=hpa@zytor.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-tip-commits@vger.kernel.org \
--cc=mikelley@microsoft.com \
--cc=mingo@kernel.org \
--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 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).