This is a note to let you know that I've just added the patch titled fpga: dfl: fme: Fix cpu hotplug issue in performance reporting to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: fpga-dfl-fme-fix-cpu-hotplug-issue-in-performance-reporting.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From ec6446d5304b3c3dd692a1e244df7e40bbb5af36 Mon Sep 17 00:00:00 2001 From: Kajol Jain <kjain@xxxxxxxxxxxxx> Date: Tue, 13 Jul 2021 13:12:16 +0530 Subject: fpga: dfl: fme: Fix cpu hotplug issue in performance reporting From: Kajol Jain <kjain@xxxxxxxxxxxxx> commit ec6446d5304b3c3dd692a1e244df7e40bbb5af36 upstream. The performance reporting driver added cpu hotplug feature but it didn't add pmu migration call in cpu offline function. This can create an issue incase the current designated cpu being used to collect fme pmu data got offline, as based on current code we are not migrating fme pmu to new target cpu. Because of that perf will still try to fetch data from that offline cpu and hence we will not get counter data. Patch fixed this issue by adding pmu_migrate_context call in fme_perf_offline_cpu function. Fixes: 724142f8c42a ("fpga: dfl: fme: add performance reporting support") Cc: stable@xxxxxxxxxxxxxxx Tested-by: Xu Yilun <yilun.xu@xxxxxxxxx> Acked-by: Wu Hao <hao.wu@xxxxxxxxx> Signed-off-by: Kajol Jain <kjain@xxxxxxxxxxxxx> Signed-off-by: Moritz Fischer <mdf@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/fpga/dfl-fme-perf.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/fpga/dfl-fme-perf.c +++ b/drivers/fpga/dfl-fme-perf.c @@ -953,6 +953,8 @@ static int fme_perf_offline_cpu(unsigned return 0; priv->cpu = target; + perf_pmu_migrate_context(&priv->pmu, cpu, target); + return 0; } Patches currently in stable-queue which might be from kjain@xxxxxxxxxxxxx are queue-5.10/fpga-dfl-fme-fix-cpu-hotplug-issue-in-performance-reporting.patch