From: Joerg Roedel <joro@8bytes.org>
To: Amol Grover <frextrite@gmail.com>
Cc: "Paul E . McKenney" <paulmck@kernel.org>,
linux-kernel@vger.kernel.org,
Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>,
Qian Cai <cai@lca.pw>, Deepa Dinamani <deepa.kernel@gmail.com>,
Joel Fernandes <joel@joelfernandes.org>,
Andrew Morton <akpm@linux-foundation.org>,
linux-kernel-mentees@lists.linuxfoundation.org,
Thomas Gleixner <tglx@linutronix.de>,
Allison Randal <allison@lohutok.net>,
Lu Baolu <baolu.lu@linux.intel.com>
Subject: Re: [Linux-kernel-mentees] [PATCH RESEND] iommu: dmar: Fix RCU list debugging warnings
Date: Mon, 2 Mar 2020 17:04:13 +0100 [thread overview]
Message-ID: <20200302160412.GA7829@8bytes.org> (raw)
In-Reply-To: <20200223165538.29870-1-frextrite@gmail.com>
On Sun, Feb 23, 2020 at 10:25:39PM +0530, Amol Grover wrote:
> dmar_drhd_units is traversed using list_for_each_entry_rcu()
> outside of an RCU read side critical section but under the
> protection of dmar_global_lock. Hence add corresponding lockdep
> expression to silence the following false-positive warnings:
>
> [ 1.603975] =============================
> [ 1.603976] WARNING: suspicious RCU usage
> [ 1.603977] 5.5.4-stable #17 Not tainted
> [ 1.603978] -----------------------------
> [ 1.603980] drivers/iommu/intel-iommu.c:4769 RCU-list traversed in non-reader section!!
>
> [ 1.603869] =============================
> [ 1.603870] WARNING: suspicious RCU usage
> [ 1.603872] 5.5.4-stable #17 Not tainted
> [ 1.603874] -----------------------------
> [ 1.603875] drivers/iommu/dmar.c:293 RCU-list traversed in non-reader section!!
>
> Tested-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
> Signed-off-by: Amol Grover <frextrite@gmail.com>
> ---
> include/linux/dmar.h | 8 +++++---
> 1 file changed, 5 insertions(+), 3 deletions(-)
Applied, thanks.
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WARNING: multiple messages have this Message-ID (diff)
From: Joerg Roedel <joro@8bytes.org>
To: Amol Grover <frextrite@gmail.com>
Cc: Allison Randal <allison@lohutok.net>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Andrew Morton <akpm@linux-foundation.org>,
Lu Baolu <baolu.lu@linux.intel.com>,
Thomas Gleixner <tglx@linutronix.de>, Qian Cai <cai@lca.pw>,
Deepa Dinamani <deepa.kernel@gmail.com>,
linux-kernel@vger.kernel.org,
linux-kernel-mentees@lists.linuxfoundation.org,
Joel Fernandes <joel@joelfernandes.org>,
Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>,
"Paul E . McKenney" <paulmck@kernel.org>
Subject: Re: [PATCH RESEND] iommu: dmar: Fix RCU list debugging warnings
Date: Mon, 2 Mar 2020 17:04:13 +0100 [thread overview]
Message-ID: <20200302160412.GA7829@8bytes.org> (raw)
In-Reply-To: <20200223165538.29870-1-frextrite@gmail.com>
On Sun, Feb 23, 2020 at 10:25:39PM +0530, Amol Grover wrote:
> dmar_drhd_units is traversed using list_for_each_entry_rcu()
> outside of an RCU read side critical section but under the
> protection of dmar_global_lock. Hence add corresponding lockdep
> expression to silence the following false-positive warnings:
>
> [ 1.603975] =============================
> [ 1.603976] WARNING: suspicious RCU usage
> [ 1.603977] 5.5.4-stable #17 Not tainted
> [ 1.603978] -----------------------------
> [ 1.603980] drivers/iommu/intel-iommu.c:4769 RCU-list traversed in non-reader section!!
>
> [ 1.603869] =============================
> [ 1.603870] WARNING: suspicious RCU usage
> [ 1.603872] 5.5.4-stable #17 Not tainted
> [ 1.603874] -----------------------------
> [ 1.603875] drivers/iommu/dmar.c:293 RCU-list traversed in non-reader section!!
>
> Tested-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
> Signed-off-by: Amol Grover <frextrite@gmail.com>
> ---
> include/linux/dmar.h | 8 +++++---
> 1 file changed, 5 insertions(+), 3 deletions(-)
Applied, thanks.
next prev parent reply other threads:[~2020-03-02 16:04 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-23 16:55 [Linux-kernel-mentees] [PATCH RESEND] iommu: dmar: Fix RCU list debugging warnings Amol Grover
2020-02-23 16:55 ` Amol Grover
2020-02-23 23:34 ` [Linux-kernel-mentees] " Lu Baolu
2020-02-23 23:34 ` Lu Baolu
2020-03-02 16:04 ` Joerg Roedel [this message]
2020-03-02 16:04 ` Joerg Roedel
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