On Mon, Mar 02, 2020 at 06:02:21PM +0100, Rafael J. Wysocki wrote:

On Mon, Mar 2, 2020 at 1:34 PM Madhuparna Bhowmik
[off-list ref] wrote:

quoted

On Mon, 2 Mar, 2020, 3:48 AM Joel Fernandes, [off-list ref] wrote:

quoted

On Sun, Mar 1, 2020 at 4:23 PM Rafael J. Wysocki [off-list ref] wrote:

quoted

On Sun, Mar 1, 2020 at 9:53 PM [off-list ref] wrote:

quoted

On March 1, 2020 3:12:53 PM EST, "Rafael J. Wysocki" [off-list ref] wrote:

quoted

On Fri, Feb 28, 2020 at 6:47 PM [off-list ref] wrote:

quoted

From: Madhuparna Bhowmik <redacted>

This patch passes the cond argument to list_for_each_entry_rcu()
to fix the following false-positive lockdep warnings:

[  330.302784] =============================
[  330.302789] WARNING: suspicious RCU usage
[  330.302796] 5.6.0-rc1+ #5 Not tainted
[  330.302801] -----------------------------
[  330.302808] drivers/base/power/main.c:326 RCU-list traversed in

non-reader section!!

quoted

[  330.303303] =============================
[  330.303307] WARNING: suspicious RCU usage
[  330.303311] 5.6.0-rc1+ #5 Not tainted
[  330.303315] -----------------------------
[  330.303319] drivers/base/power/main.c:1698 RCU-list traversed in

non-reader section!!

quoted

[  331.934969] =============================
[  331.934971] WARNING: suspicious RCU usage
[  331.934973] 5.6.0-rc1+ #5 Not tainted
[  331.934975] -----------------------------
[  331.934977] drivers/base/power/main.c:1238 RCU-list traversed in

non-reader section!!

quoted

[  332.467772] WARNING: suspicious RCU usage
[  332.467775] 5.6.0-rc1+ #5 Not tainted
[  332.467775] -----------------------------
[  332.467778] drivers/base/power/main.c:269 RCU-list traversed in

non-reader section!!

I don't see these warnings in the kernels run locally here.

What do you do to get them?

Joel, any comments here?

You have to enable lockdep in your config. Does your setup have that?

CONFIG_LOCK_DEBUGGING_SUPPORT=y
CONFIG_PROVE_LOCKING=y
CONFIG_DEBUG_SPINLOCK=y
CONFIG_DEBUG_LOCK_ALLOC=y
CONFIG_LOCKDEP=y

I had CONFIG_PROVE_RCU_LIST = y and I think these warnings were triggered when I had closed my laptop (like just close without shutting down).

OK, so let's define a macro for that in this file to avoid code duplication.

And analogously in the second patch.

Sure, I will do it and send the patch soon.

Thanks!

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