From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-187.mta1.migadu.com (out-187.mta1.migadu.com [95.215.58.187]) (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 4A6E417D2 for ; Fri, 22 Aug 2025 00:02:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.187 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755820939; cv=none; b=j+VjnuDha8sT2mRcjimCyet45BMsXY0JQZhWg2pVyqlf0AxVFKfO4CVm5COrytW+WRLoK5wxANXwlGsb0TobNZtetELCKUzLz5kNOZtZ0OZOu1lr1SZxzXV2uaSMAvsYguj22oImkdp+nClx3Y6X3/fDcWzHbtmOMmOBkOw7/Xc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755820939; c=relaxed/simple; bh=sB2kd2IaQcw0g1s75bnvdgvxVgOn/b5tYJ5GTBFylKA=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=pAuFeq+RC6kwEVniBY6wqa3nmUS51poVady5Jh5fQWH9Uc71EYdTBsHIpOteJcxlLa/jz8WJLR1wcwAVKPd01IcGt8ouC1DhbyIkY+J+DK/XBT+1e1VNusrk864OOhZzkIvGMyXEkakVAqxj2zj5OuKI1I4h/r4N8RN3wHQxMHo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=OGn+aToK; arc=none smtp.client-ip=95.215.58.187 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="OGn+aToK" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1755820933; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=vUrDaGrlbnJZ+oxdBPVH9aUM2aDAG/pXEN+zcLc/AKw=; b=OGn+aToKUF9886Yb2+U4Tf4NouYzRT+l0M8RBeJjCeLgRpw/Fg7v7pIWjH8xuOxNXujSre vgZxqRSelB7SwT30XZBByV7+Pkd8uDKRe2KYir6r6sXfvWWm5QSsGIROsD5Vij6NSvnqGj oh3k3Bh3d4B/2G8UaLzDmtNLOdDTI48= From: Oliver Upton To: Marc Zyngier , Raghavendra Rao Ananta Cc: Oliver Upton , Mingwei Zhang , linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, kvm@vger.kernel.org Subject: Re: [PATCH v2 0/2] KVM: arm64: Reschedule as needed when destroying the stage-2 page-tables Date: Thu, 21 Aug 2025 17:02:00 -0700 Message-Id: <175582091313.1266576.4329884314263043118.b4-ty@linux.dev> In-Reply-To: <20250820162242.2624752-1-rananta@google.com> References: <20250820162242.2624752-1-rananta@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT On Wed, 20 Aug 2025 16:22:40 +0000, Raghavendra Rao Ananta wrote: > When destroying a fully-mapped 128G VM abruptly, the following scheduler > warning is observed: > > sched: CPU 0 need_resched set for > 100018840 ns (100 ticks) without schedule > CPU: 0 UID: 0 PID: 9617 Comm: kvm_page_table_ Tainted: G O 6.16.0-smp-DEV #3 NONE > Tainted: [O]=OOT_MODULE > Call trace: > show_stack+0x20/0x38 (C) > dump_stack_lvl+0x3c/0xb8 > dump_stack+0x18/0x30 > resched_latency_warn+0x7c/0x88 > sched_tick+0x1c4/0x268 > update_process_times+0xa8/0xd8 > tick_nohz_handler+0xc8/0x168 > __hrtimer_run_queues+0x11c/0x338 > hrtimer_interrupt+0x104/0x308 > arch_timer_handler_phys+0x40/0x58 > handle_percpu_devid_irq+0x8c/0x1b0 > generic_handle_domain_irq+0x48/0x78 > gic_handle_irq+0x1b8/0x408 > call_on_irq_stack+0x24/0x30 > do_interrupt_handler+0x54/0x78 > el1_interrupt+0x44/0x88 > el1h_64_irq_handler+0x18/0x28 > el1h_64_irq+0x84/0x88 > stage2_free_walker+0x30/0xa0 (P) > __kvm_pgtable_walk+0x11c/0x258 > __kvm_pgtable_walk+0x180/0x258 > __kvm_pgtable_walk+0x180/0x258 > __kvm_pgtable_walk+0x180/0x258 > kvm_pgtable_walk+0xc4/0x140 > kvm_pgtable_stage2_destroy+0x5c/0xf0 > kvm_free_stage2_pgd+0x6c/0xe8 > kvm_uninit_stage2_mmu+0x24/0x48 > kvm_arch_flush_shadow_all+0x80/0xa0 > kvm_mmu_notifier_release+0x38/0x78 > __mmu_notifier_release+0x15c/0x250 > exit_mmap+0x68/0x400 > __mmput+0x38/0x1c8 > mmput+0x30/0x68 > exit_mm+0xd4/0x198 > do_exit+0x1a4/0xb00 > do_group_exit+0x8c/0x120 > get_signal+0x6d4/0x778 > do_signal+0x90/0x718 > do_notify_resume+0x70/0x170 > el0_svc+0x74/0xd8 > el0t_64_sync_handler+0x60/0xc8 > el0t_64_sync+0x1b0/0x1b8 > > [...] Applied to fixes, thanks! [1/2] KVM: arm64: Split kvm_pgtable_stage2_destroy() https://git.kernel.org/kvmarm/kvmarm/c/0e89ca13ee5f [2/2] KVM: arm64: Reschedule as needed when destroying the stage-2 page-tables https://git.kernel.org/kvmarm/kvmarm/c/e9abe311f356 -- Best, Oliver