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13:56:35.0903 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: d9995866-0d9b-4251-8315-093f062abab4 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 5TWMGqkXrHcDXZ63NKn4ofhHAxt1xYi7Sjqx+BQYq4sp37n3dLGq7Duo67Yk2qMnpnMubMVzZBJQF0XciY7mwal6djI1rVSGanj6GlHIY6g= X-MS-Exchange-Transport-CrossTenantHeadersStamped: GV0P278MB0018 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: toradex.com Content-Type: text/plain; charset=WINDOWS-1252 Content-Disposition: inline Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Wed, Sep 07, 2022 at 04:39:15PM +0200, Marc Kleine-Budde wrote: > On 05.09.2022 09:38:04, Marc Kleine-Budde wrote: > > On 9/1/22 4:04 PM, Csókás Bence wrote: > > > Mutexes cannot be taken in a non-preemptible context, > > > causing a panic in `fec_ptp_save_state()`. Replacing > > > `ptp_clk_mutex` by `tmreg_lock` fixes this. > > > > I was on holidays, but this doesn't look good. > > Does anyone care to fix this? Csókás? I do care, however I do not really have resources for anything better than reverting both of the problematic commits. If we do not have a fix, I guess this is the only way. Csókás? For some reason when I tested on imx6 :-( I had no warning, now the change was merged and while doing a quick test on a imx7 I got new issues. [ 37.061582] ======================================================== [ 37.070203] WARNING: possible irq lock inversion dependency detected [ 37.078847] 6.0.0-rc4-00137-g506357871c18 #3 Tainted: G W [ 37.087944] -------------------------------------------------------- [ 37.096615] systemd/580 just changed the state of lock: [ 37.104160] c218f2a4 (&dev->tx_global_lock){+.-.}-{2:2}, at: dev_watchdog+0x18/0x2c4 [ 37.116691] but this lock took another, SOFTIRQ-unsafe lock in the past: [ 37.125896] (&fep->tmreg_lock){+.+.}-{2:2} [ 37.125921] [ 37.125921] [ 37.125921] and interrupts could create inverse lock ordering between them. [ 37.125921] [ 37.153018] [ 37.153018] other info that might help us debug this: [ 37.163824] Possible interrupt unsafe locking scenario: [ 37.163824] [ 37.174714] CPU0 CPU1 [ 37.181215] ---- ---- [ 37.187631] lock(&fep->tmreg_lock); [ 37.193110] local_irq_disable(); [ 37.200841] lock(&dev->tx_global_lock); [ 37.209153] lock(&fep->tmreg_lock); [ 37.217061] [ 37.221328] lock(&dev->tx_global_lock); [ 37.227167] [ 37.227167] *** DEADLOCK *** that just goes away reverting this patch. Francesco