RE: [PATCH v2 1/2] soc: fsl: qbman: Always disable interrupts when taking cgr_lock
> -Original Message- > From: Sean Anderson > Sent: Monday, April 3, 2023 18:22 > To: Vladimir Oltean > Cc: Leo Li ; linuxppc-dev@lists.ozlabs.org; linux-arm- > ker...@lists.infradead.org; Scott Wood ; Camelia > Alexandra Groza ; linux-ker...@vger.kernel.org; > Roy Pledge ; David S . Miller > ; Claudiu Manoil > Subject: Re: [PATCH v2 1/2] soc: fsl: qbman: Always disable interrupts when > taking cgr_lock > > On 4/3/23 10:02, Vladimir Oltean wrote: > > On Fri, Mar 31, 2023 at 11:14:12AM -0400, Sean Anderson wrote: > >> smp_call_function_single disables IRQs when executing the callback. To > >> prevent deadlocks, we must disable IRQs when taking cgr_lock elsewhere. > >> This is already done by qman_update_cgr and qman_delete_cgr; fix the > >> other lockers. > >> > >> Fixes: c535e923bb97 ("soc/fsl: Introduce DPAA 1.x QMan device driver") > > > > If you've identified smp_call_function_single() as the problem, then the > > true issue seems to lie in commit 96f413f47677 ("soc/fsl/qbman: fix > > issue in qman_delete_cgr_safe()") and not in the initial commit, no? > > Yes, that seems better. I did a blame and saw that qman_delete_cgr_safe > had been around since the initial driver, but I didn't realize it worked > in a different way back then. > > --Sean > > > Anyway, > > > > Tested-by: Vladimir Oltean Apart from Vladimir's comment: Reviewed-by: Camelia Groza
Re: [PATCH v2 1/2] soc: fsl: qbman: Always disable interrupts when taking cgr_lock
On 4/3/23 10:02, Vladimir Oltean wrote: > On Fri, Mar 31, 2023 at 11:14:12AM -0400, Sean Anderson wrote: >> smp_call_function_single disables IRQs when executing the callback. To >> prevent deadlocks, we must disable IRQs when taking cgr_lock elsewhere. >> This is already done by qman_update_cgr and qman_delete_cgr; fix the >> other lockers. >> >> Fixes: c535e923bb97 ("soc/fsl: Introduce DPAA 1.x QMan device driver") > > If you've identified smp_call_function_single() as the problem, then the > true issue seems to lie in commit 96f413f47677 ("soc/fsl/qbman: fix > issue in qman_delete_cgr_safe()") and not in the initial commit, no? Yes, that seems better. I did a blame and saw that qman_delete_cgr_safe had been around since the initial driver, but I didn't realize it worked in a different way back then. --Sean > Anyway, > > Tested-by: Vladimir Oltean
Re: [PATCH v2 1/2] soc: fsl: qbman: Always disable interrupts when taking cgr_lock
On Fri, Mar 31, 2023 at 11:14:12AM -0400, Sean Anderson wrote: > smp_call_function_single disables IRQs when executing the callback. To > prevent deadlocks, we must disable IRQs when taking cgr_lock elsewhere. > This is already done by qman_update_cgr and qman_delete_cgr; fix the > other lockers. > > Fixes: c535e923bb97 ("soc/fsl: Introduce DPAA 1.x QMan device driver") If you've identified smp_call_function_single() as the problem, then the true issue seems to lie in commit 96f413f47677 ("soc/fsl/qbman: fix issue in qman_delete_cgr_safe()") and not in the initial commit, no? Anyway, Tested-by: Vladimir Oltean