On Mon, Dec 11, 2017 at 01:04:58PM -0600, Corey Minyard wrote: > On 11/29/2017 05:13 PM, Julia Cartwright wrote: > > Hello RT Folks! > > > > I'm pleased to announce the 4.1.46-rt52 stable release. > > > > You can get this release via the git tree at: > > > > git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-stable-rt.git > > > > branch: v4.1-rt > > Head SHA1: 6e737a91c1ce923d4e10db831e14cfef9a2459cc > > > > Or to build 4.1.46-rt52 directly, the following patches should be applied: > > > > https://urldefense.proofpoint.com/v2/url?u=http-3A__www.kernel.org_pub_linux_kernel_v4.x_linux-2D4.1.tar.xz&d=DwICaQ&c=I_0YwoKy7z5LMTVdyO6YCiE2uzI1jjZZuIPelcSjixA&r=cAXq_8W9Othb2h8ZcWv8Vw&m=a5KTpX9A0-pHwmQkOOLr5_xeWPavI-lgN7Z0Goes2So&s=tGmSNpZKEKvhTpeVu_ktmD4I5PIXfIJhZ79DxwbCjtQ&e= > > > > https://urldefense.proofpoint.com/v2/url?u=http-3A__www.kernel.org_pub_linux_kernel_v4.x_patch-2D4.1.46.xz&d=DwICaQ&c=I_0YwoKy7z5LMTVdyO6YCiE2uzI1jjZZuIPelcSjixA&r=cAXq_8W9Othb2h8ZcWv8Vw&m=a5KTpX9A0-pHwmQkOOLr5_xeWPavI-lgN7Z0Goes2So&s=hx9pHgRy7tWhUeeiJhPOH0T8qdDrhtZvWxOWuIBZZgs&e= > > > > https://urldefense.proofpoint.com/v2/url?u=http-3A__www.kernel.org_pub_linux_kernel_projects_rt_4.1_patch-2D4.1.46-2Drt52.patch.xz&d=DwICaQ&c=I_0YwoKy7z5LMTVdyO6YCiE2uzI1jjZZuIPelcSjixA&r=cAXq_8W9Othb2h8ZcWv8Vw&m=a5KTpX9A0-pHwmQkOOLr5_xeWPavI-lgN7Z0Goes2So&s=Pm8ed_xvW1drpPxNkt035bj6ILvSImuN9vvgEAt8IiM&e= > > > > > > You can also build from 4.1.46-rt51 by applying the incremental patch: > > > > https://urldefense.proofpoint.com/v2/url?u=http-3A__www.kernel.org_pub_linux_kernel_projects_rt_4.1_incr_patch-2D4.1.46-2Drt51-2Drt52.patch.xz&d=DwICaQ&c=I_0YwoKy7z5LMTVdyO6YCiE2uzI1jjZZuIPelcSjixA&r=cAXq_8W9Othb2h8ZcWv8Vw&m=a5KTpX9A0-pHwmQkOOLr5_xeWPavI-lgN7Z0Goes2So&s=ZM64-JCd0WNFQgFlB3wbCfn8Jtf9rq5QyCO2-GJsC2Q&e= > > > > Enjoy! > > Julia > > > > Changes from v4.1.46-rt51: > > --- > > Julia Cartwright (2): > > workqueue: fixup rcu check for RT > > Linux 4.1.46-rt52 > > > > Sebastian Andrzej Siewior (2): > > PM / CPU: replace raw_notifier with atomic_notifier (fixup) > > This change breaks the compile of 4.1 on ARM (and other things using > kernel/cpu_pm.c). > > rcu_irq_enter_irqson() and friends doesn't exist in 4.1. In fact, > rcu_irq_enter() doesn't even exist. > > Sorry I didn't get to testing this earlier, I've been focused on other things. Thanks! My current builds apparently don't currently cover CPU_PM builds, so I didn't see this :(. Thanks for the report. v4.1 does contain rcu_irq_enter(), and it looks like what we should be using in 4.1 instead. I'm thinking the below should be okay; I'll be standing up a proper cpu hotplugging test to give it some runtime. Thanks, Julia -- 8< -- Subject: [PATCH] PM / CPU: replace usage of rcu_irq_{enter,exit}_irqson() Commit c50243950f97e ("PM / CPU: replace raw_notifier with atomic_notifier (fixup)") intended to fix up RCU usage in idle, by telling RCU to pay attention. However, the cherry-pick back from rt-devel included the invocation of the _irqson() variants of rcu_irq_{enter,exit}() API which doesn't exist in 4.1. For 4.1, just simply drop the _irqson() variant, and instead use rcu_irq_{enter,exit}() directly instead. This is safe, because in 4.1, these functions internally disable interrupts. Reported-by: Corey Minyard <cminyard@xxxxxxxxxx> Signed-off-by: Julia Cartwright <julia@xxxxxx --- kernel/cpu_pm.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/cpu_pm.c b/kernel/cpu_pm.c index d1d1c3961553..eeff3c382793 100644 --- a/kernel/cpu_pm.c +++ b/kernel/cpu_pm.c @@ -33,10 +33,10 @@ static int cpu_pm_notify(enum cpu_pm_event event, int nr_to_call, int *nr_calls) * could be disfunctional in cpu idle. Copy RCU_NONIDLE code to let * RCU know this. */ - rcu_irq_enter_irqson(); + rcu_irq_enter(); ret = __atomic_notifier_call_chain(&cpu_pm_notifier_chain, event, NULL, nr_to_call, nr_calls); - rcu_irq_exit_irqson(); + rcu_irq_exit(); return notifier_to_errno(ret); } -- 2.14.2 -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
