From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DE9CE1E0B7C; Tue, 7 Jan 2025 11:56:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736250972; cv=none; b=ZPRQ1GNhu4AXSrt1c24hvOByK8+T6lVu/kKJL/sH98FmOCjln/Qw33H4+LG9Or/SHJjgCB3ISFRqQjs0SZ1HHVee4Yw3uhclAb/EeOeUqKDf5SofIR0n18PXev3jarjwe2pc8wxawU7DLhVT9jtZOA76drw22hMWjSSv+ZyzWhA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736250972; c=relaxed/simple; bh=vSp+fhNJx7hcAWw5M6HPzbQqsL3TPjKtX9nO1km2Fs0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=t5j+nM2RDbwbzXNUnfaaXGgRbp5+cRNoVzKMyecEMhScYjq1XFGbmdTfz+jOpcoRSh6lVZwTi0fygrPxuG4nDTcft34TBhVxIfKKVFWTlzK9IgLWX6ZgSfFMqtulvsPPkq0qubyalTxpD10I7XrImtfOJu6K9XpxGafgq6FkO/E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=M9ikX6Jw; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=jM9IXPU6; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="M9ikX6Jw"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="jM9IXPU6" Date: Tue, 7 Jan 2025 12:56:06 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1736250967; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=24gVf7tG/7zFXxMSeeWEt175mRZT2bbtN+ldqrE2Be8=; b=M9ikX6Jw0SAd6j6flhMcgyKR1487gztDffuAkIyZk4pBf0peAJKBK/3XfiyK+FVOEr3M/O Uic0yCFsZb9qAqGql5LRxqzVxb/8xLB7F3quA5JhVLVQm0YHqh/ScBA0LUu/tE1h5eTOr9 dcrA35Zj/0nXXOh/GDHMWezLlD+e94r1gRlekT66o8HbFd9X8ZqHSIbI/BHxQ2jEV94y30 fiKa3zmXIO48ZS1dE49jQXRehtbzUgp13DQnxtW7i5KQ6aIRYSg/dn7CvnzUk5QG2EWH4h vHvNgrz7prGbcaQoDdhV5v0VKGjf5tZ5RFq0+Dz+T87U3Nbyh5s5qALh/AJRBw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1736250967; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=24gVf7tG/7zFXxMSeeWEt175mRZT2bbtN+ldqrE2Be8=; b=jM9IXPU68JkcdgaRhlA6nHJEUlXxpuZiXLB7a7FT3zk4OokcHe3dQ4Pwqw0PuwFDL4s7C7 La7hHj8BUpuXQDAg== From: Sebastian Andrzej Siewior To: Robert Joslyn Cc: linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org, tglx@linutronix.de, rostedt@goodmis.org, Shrikanth Hegde Subject: Re: [PATCH] powerpc: Allow scheduling of IRQ with PREEMPT_RT Message-ID: <20250107115606.q67--i0f@linutronix.de> References: <20241226191238.2559880-1-robert_joslyn@selinc.com> Precedence: bulk X-Mailing-List: linux-rt-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20241226191238.2559880-1-robert_joslyn@selinc.com> On 2024-12-26 11:12:38 [-0800], Robert Joslyn wrote: > This branch is needed to allow preemptible IRQs to be scheduled, > otherwise the kernel hangs during boot on my e300 based platforms. > This branch is needed for both CONFIG_PREEMPT and CONFIG_PREEMPT_RT, > so broaden the check to CONFIG_PREEMPTION, which is selected by both. > > This was previously set to CONFIG_PREEMPTION, but was reverted as part > of removing LAZY_PREEMPT support. I remember I pointed this out while Shrikanth posted the preempt-lazy patches but didn't realize that I need this in RT tree, too. The lazy-preempt patches for powerpc were merged upstream, I am going to pull them into the v6.6-series. I am going to Cc you, hopefully you can confirm that it is working. > Fixes: b33022a48c79 > Signed-off-by: Robert Joslyn > --- > arch/powerpc/kernel/interrupt.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c > index af62ec974b97..970039af8e92 100644 > --- a/arch/powerpc/kernel/interrupt.c > +++ b/arch/powerpc/kernel/interrupt.c > @@ -396,7 +396,7 @@ notrace unsigned long interrupt_exit_kernel_prepare(struct pt_regs *regs) > /* Returning to a kernel context with local irqs enabled. */ > WARN_ON_ONCE(!(regs->msr & MSR_EE)); > again: > - if (IS_ENABLED(CONFIG_PREEMPT)) { > + if (IS_ENABLED(CONFIG_PREEMPTION)) { > /* Return to preemptible kernel context */ > if (unlikely(read_thread_flags() & _TIF_NEED_RESCHED)) { > if (preempt_count() == 0) Sebastian