From patchwork Fri Apr 11 07:37:33 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nam Cao X-Patchwork-Id: 14047768 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8ED35C36010 for ; Fri, 11 Apr 2025 07:42:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=X+UQEszhhyx5orvv0upRMEVuQLmNZT576sheEcGpELI=; b=SbCBygDKO4q727W5TS+RqbGdDX hDB33wXSgkC0zmhxMI7u2PCXCLR/5ozeZqeitZQuEkFZC44Q1+ZXTQ+Y9RGxQ7CryvbLBsdc4DZ6S l+0r5DFTsPt1alBZB/V6buZE8Ij4dKWfSa9Ht5ph+Y13Ug2I7ozUCEy/zjKt03DphHkK/9M9pTfPn BHUMcskEVOp1+sIX7+oaT1viSZ9EtJwAoGuXkuTgPgv432/UJ+mDaFfn+HSUu5TJTc6T9Yb6v4BwT D9IwyvFxvISrEmzLEIR4fsqmvlCLM7xMSH6fy5JpY7Ejxei+DbLuDtCzruWiFcnVzl3W6AIKeuP8I rDk5Czcg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1u391M-0000000CuYV-3YLD; Fri, 11 Apr 2025 07:41:52 +0000 Received: from galois.linutronix.de ([2a0a:51c0:0:12e:550::1]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1u38xp-0000000CtxK-3mYG for linux-arm-kernel@lists.infradead.org; Fri, 11 Apr 2025 07:38:15 +0000 From: Nam Cao DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1744357092; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=X+UQEszhhyx5orvv0upRMEVuQLmNZT576sheEcGpELI=; b=f4DJbwmzrkW7mPK9AHeAMNkaHKQb6i9D8wE+SjlI+6clttDzOXS+BH/xxNfaZnijDwvdOt o7eAVGZ+a1CE4f/4FkFqOxnwC9JVHPkMXqvimm41ko07kwtSwv6CcXwyYcRUMcuWrB4yO1 WDpXcU36HnTCzuCfTd19Z/x6xdlaWhad04mswouMPSJHfhCHiPJBAOTNMdJvQdlgXiAIKC lgNEG17P4M9QKvyTvrBr2oMMyWGHeolQyB66jng4iaN2IzNfFpgjNA7k07Awn5B9rL9559 klyZS1lhgO3nlRb0g9jCzNmW9t2xoCiDwbTYl1vzuq9M8geXllHaL7D+J0CMjg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1744357092; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=X+UQEszhhyx5orvv0upRMEVuQLmNZT576sheEcGpELI=; b=q7ZNzw7KLTD8TrmZLui1q3zZXO8wwN74y0sMcI8jWDUU/BiH5Q1vArAYZTTz/JIp9gH6Ok sOiFNeZHbpm2KzDg== To: Steven Rostedt , Gabriele Monaco , linux-trace-kernel@vger.kernel.org, linux-kernel@vger.kernel.org Cc: john.ogness@linutronix.de, Nam Cao , Catalin Marinas , Will Deacon , linux-arm-kernel@lists.infradead.org Subject: [PATCH v2 17/22] arm64: mm: Add page fault trace points Date: Fri, 11 Apr 2025 09:37:33 +0200 Message-Id: <952afa13306026813a5731703d6a86fb48f4ccf8.1744355018.git.namcao@linutronix.de> In-Reply-To: References: MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250411_003814_080844_9A7D92B7 X-CRM114-Status: UNSURE ( 9.99 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Add page fault trace points, which are useful to implement RV monitor which watches page faults. Signed-off-by: Nam Cao --- Cc: Catalin Marinas Cc: Will Deacon Cc: linux-arm-kernel@lists.infradead.org --- arch/arm64/mm/fault.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index ef63651099a9..e3f096b0dffd 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -44,6 +44,9 @@ #include #include +#define CREATE_TRACE_POINTS +#include + struct fault_info { int (*fn)(unsigned long far, unsigned long esr, struct pt_regs *regs); @@ -559,6 +562,11 @@ static int __kprobes do_page_fault(unsigned long far, unsigned long esr, if (kprobe_page_fault(regs, esr)) return 0; + if (user_mode(regs)) + trace_page_fault_user(addr, regs, esr); + else + trace_page_fault_kernel(addr, regs, esr); + /* * If we're in an interrupt or have no user context, we must not take * the fault. From patchwork Fri Apr 11 07:37:35 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nam Cao X-Patchwork-Id: 14047769 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id AD408C369A2 for ; Fri, 11 Apr 2025 07:43:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=RBmDrhu0Y2boD5jF26ggcoAtTCTRqgDeFKAQWZPdoF8=; b=KrHr7dlGvQx7uzXcq7KJ4Wuwdf 61iihcgM78lRZBr2A9Mnf++tEAIm1H2YGjSpGrAcoH+7LqSPtLZ4ZT2zPAHNqV7uhbMJNc++EdJIu +ZMKi18ELtkpx/Yo3C6puWAZnvXBihVWkZNlby4tA+u3FOecv0qHUaZg1Se7JlbMfsVyaPdxFHq20 MypAs/6cRNV+exOYQuyut84g+eKioLDl9a/TgBKlAFkv3ZpzKenGjo1xgS+FTDbqAw4Jv6HAPPekU hjk2UJVQORgqM54SzhONjjJfJuMGh1rdH8xaAcsYbYDW8CgcoQ7QMwtXBHU7fhtc8zBJ1B4vzcONB 15zLsJSA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1u3939-0000000Cv1l-3aNd; Fri, 11 Apr 2025 07:43:43 +0000 Received: from desiato.infradead.org ([2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1u38xv-0000000CtzU-1Cnh; Fri, 11 Apr 2025 07:38:19 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Content-Transfer-Encoding:MIME-Version :References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=RBmDrhu0Y2boD5jF26ggcoAtTCTRqgDeFKAQWZPdoF8=; b=SRy9eViUX0f7BdhoDYCATlzKdx J9t4bIEKYOZJc3TZ892wCC7XIe1nV/1VvB94XYD7CV3lSd8c2jS2mFeDaUSWnSWraymIwxhYRGdOb HXSIYrz5SvX36Wv2Hd7TfvF2UtyCVtu4hgb4RJxvno5RqVoALSzaH16dy0bVRvd5lXPiG013K4RwD Wx421wgRBCJNRVEW0uIhpI5AfOifyT1qF6Vtx2ctkAhExXHMFRb2A01jegP1Rp/OHKGDagguYu7sD uXAwjcGlFeghrIpFzERVCIvbNkhURw5IUjIpS0evtOdlIBWZoBvNKkOj+XIvVhxlvJdGrABCF8voy cJ6ccLhA==; Received: from galois.linutronix.de ([2a0a:51c0:0:12e:550::1]) by desiato.infradead.org with esmtps (Exim 4.98.1 #2 (Red Hat Linux)) id 1u38xs-00000008xvu-1E0e; Fri, 11 Apr 2025 07:38:18 +0000 From: Nam Cao DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1744357093; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=RBmDrhu0Y2boD5jF26ggcoAtTCTRqgDeFKAQWZPdoF8=; b=b5qttIrpDkpQwlivCD+hVWgAfFUwB2Gw2Ji6eC1nGW1frRf7lrpPulX7Ta/qotxELABNax cJmLzn7Y7xtVgnlsv6+3SYQUmeydQYPSyajeJFwBp9eGBZxOULseYDd5gE8XdPu3Gyi1Ip r+DEtnTtHvtKiTCX1iUUmCrEpG8vahyobdd36/yFnHG2gLXlS2Kes0NeJ2haf8p+Ih7G49 Mtcxwa8PqtVLa7nHuyJrPeE6Q7H6zwJJRefRfnPS1XqY6r9FlUlbd6kzbXuoWDxUyUOghR AlaJeWr0ZemjgOJrqsTJFAAnZyuam93VFvkdlhPCyH6Y84hg4ZMYzay6MK/+eQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1744357093; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=RBmDrhu0Y2boD5jF26ggcoAtTCTRqgDeFKAQWZPdoF8=; b=1Q1+UFco+iXSwfZiKaZv1A/TWlXNwzatkGQwlapQSNGthsLfDmgU3qmIZtezT05bLF5BvP 5hrip2WfW9EKPoBw== To: Steven Rostedt , Gabriele Monaco , linux-trace-kernel@vger.kernel.org, linux-kernel@vger.kernel.org Cc: john.ogness@linutronix.de, Nam Cao , Catalin Marinas , Will Deacon , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H . Peter Anvin" , Andy Lutomirski , Peter Zijlstra , linux-arm-kernel@lists.infradead.org, linux-riscv@lists.infradead.org Subject: [PATCH v2 19/22] rv: Add rtapp_pagefault monitor Date: Fri, 11 Apr 2025 09:37:35 +0200 Message-Id: In-Reply-To: References: MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250411_083816_580162_AB348104 X-CRM114-Status: GOOD ( 18.78 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Userspace real-time applications may have design flaws that they raise page faults in real-time threads, and thus have unexpected latencies. Add an linear temporal logic monitor to detect this scenario. Signed-off-by: Nam Cao --- Cc: Catalin Marinas Cc: Will Deacon Cc: Paul Walmsley Cc: Palmer Dabbelt Cc: Albert Ou Cc: Alexandre Ghiti Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Dave Hansen Cc: x86@kernel.org Cc: H. Peter Anvin Cc: Andy Lutomirski Cc: Peter Zijlstra Cc: linux-arm-kernel@lists.infradead.org Cc: linux-riscv@lists.infradead.org --- kernel/trace/rv/Kconfig | 1 + kernel/trace/rv/Makefile | 1 + kernel/trace/rv/monitors/pagefault/Kconfig | 11 +++ .../trace/rv/monitors/pagefault/pagefault.c | 83 +++++++++++++++++++ .../trace/rv/monitors/pagefault/pagefault.h | 57 +++++++++++++ .../rv/monitors/pagefault/pagefault_trace.h | 14 ++++ kernel/trace/rv/rv_trace.h | 1 + tools/verification/models/rtapp/pagefault.ltl | 1 + 8 files changed, 169 insertions(+) create mode 100644 kernel/trace/rv/monitors/pagefault/Kconfig create mode 100644 kernel/trace/rv/monitors/pagefault/pagefault.c create mode 100644 kernel/trace/rv/monitors/pagefault/pagefault.h create mode 100644 kernel/trace/rv/monitors/pagefault/pagefault_trace.h create mode 100644 tools/verification/models/rtapp/pagefault.ltl diff --git a/kernel/trace/rv/Kconfig b/kernel/trace/rv/Kconfig index 5c407d291661..6f86d8501e87 100644 --- a/kernel/trace/rv/Kconfig +++ b/kernel/trace/rv/Kconfig @@ -42,6 +42,7 @@ source "kernel/trace/rv/monitors/scpd/Kconfig" source "kernel/trace/rv/monitors/snep/Kconfig" source "kernel/trace/rv/monitors/sncid/Kconfig" source "kernel/trace/rv/monitors/rtapp/Kconfig" +source "kernel/trace/rv/monitors/pagefault/Kconfig" # Add new monitors here config RV_REACTORS diff --git a/kernel/trace/rv/Makefile b/kernel/trace/rv/Makefile index 9b28c2419995..353ecf939d0e 100644 --- a/kernel/trace/rv/Makefile +++ b/kernel/trace/rv/Makefile @@ -13,6 +13,7 @@ obj-$(CONFIG_RV_MON_SCPD) += monitors/scpd/scpd.o obj-$(CONFIG_RV_MON_SNEP) += monitors/snep/snep.o obj-$(CONFIG_RV_MON_SNCID) += monitors/sncid/sncid.o obj-$(CONFIG_RV_MON_RTAPP) += monitors/rtapp/rtapp.o +obj-$(CONFIG_RV_MON_PAGEFAULT) += monitors/pagefault/pagefault.o # Add new monitors here obj-$(CONFIG_RV_REACTORS) += rv_reactors.o obj-$(CONFIG_RV_REACT_PRINTK) += reactor_printk.o diff --git a/kernel/trace/rv/monitors/pagefault/Kconfig b/kernel/trace/rv/monitors/pagefault/Kconfig new file mode 100644 index 000000000000..b31dee208459 --- /dev/null +++ b/kernel/trace/rv/monitors/pagefault/Kconfig @@ -0,0 +1,11 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +config RV_MON_PAGEFAULT + depends on RV + select RV_LTL_MONITOR + depends on RV_MON_RTAPP + default y + select LTL_MON_EVENTS_ID + bool "pagefault monitor" + help + Monitor that real-time tasks do not raise page faults diff --git a/kernel/trace/rv/monitors/pagefault/pagefault.c b/kernel/trace/rv/monitors/pagefault/pagefault.c new file mode 100644 index 000000000000..9f7a4cba39a1 --- /dev/null +++ b/kernel/trace/rv/monitors/pagefault/pagefault.c @@ -0,0 +1,83 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include +#include +#include + +#define MODULE_NAME "pagefault" + +#include +#include +#include + +#include "pagefault.h" +#include + +static void ltl_atoms_fetch(struct task_struct *task, struct ltl_monitor *mon) +{ + ltl_atom_set(mon, LTL_RT, rt_task(task)); +} + +static void ltl_atoms_init(struct task_struct *task, struct ltl_monitor *mon, bool task_creation) +{ + if (task_creation) + ltl_atom_set(mon, LTL_PAGEFAULT, false); +} + +static void handle_page_fault(void *data, unsigned long address, struct pt_regs *regs, + unsigned long error_code) +{ + ltl_atom_pulse(current, LTL_PAGEFAULT, true); +} + +static int enable_pagefault(void) +{ + int retval; + + retval = ltl_monitor_init(); + if (retval) + return retval; + + rv_attach_trace_probe("pagefault", page_fault_kernel, handle_page_fault); + rv_attach_trace_probe("pagefault", page_fault_user, handle_page_fault); + + return 0; +} + +static void disable_pagefault(void) +{ + rv_pagefault.enabled = 0; + + rv_detach_trace_probe("rtapp_pagefault", page_fault_kernel, handle_page_fault); + rv_detach_trace_probe("rtapp_pagefault", page_fault_user, handle_page_fault); + + ltl_monitor_destroy(); +} + +static struct rv_monitor rv_pagefault = { + .name = "pagefault", + .description = "Monitor that RT tasks do not raise page faults", + .enable = enable_pagefault, + .disable = disable_pagefault, +}; + +static int __init register_pagefault(void) +{ + rv_register_monitor(&rv_pagefault, &rv_rtapp); + return 0; +} + +static void __exit unregister_pagefault(void) +{ + rv_unregister_monitor(&rv_pagefault); +} + +module_init(register_pagefault); +module_exit(unregister_pagefault); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Nam Cao "); +MODULE_DESCRIPTION("pagefault: Monitor that RT tasks do not raise page faults"); diff --git a/kernel/trace/rv/monitors/pagefault/pagefault.h b/kernel/trace/rv/monitors/pagefault/pagefault.h new file mode 100644 index 000000000000..f4535c83f7d1 --- /dev/null +++ b/kernel/trace/rv/monitors/pagefault/pagefault.h @@ -0,0 +1,57 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#include + +#define MONITOR_NAME pagefault + +enum ltl_atom { + LTL_PAGEFAULT, + LTL_RT, + LTL_NUM_ATOM +}; +static_assert(LTL_NUM_ATOM <= RV_MAX_LTL_ATOM); + +static const char *ltl_atom_str(enum ltl_atom atom) +{ + static const char *const names[] = { + "p", + "r", + }; + + return names[atom]; +} + +enum ltl_buchi_state { + S0, + RV_NUM_BA_STATES +}; +static_assert(RV_NUM_BA_STATES <= RV_MAX_BA_STATES); + +static void ltl_start(struct task_struct *task, struct ltl_monitor *mon) +{ + bool pagefault = test_bit(LTL_PAGEFAULT, mon->atoms); + bool val3 = !pagefault; + bool rt = test_bit(LTL_RT, mon->atoms); + bool val1 = !rt; + bool val4 = val1 || val3; + + if (val4) + __set_bit(S0, mon->states); +} + +static void +ltl_possible_next_states(struct ltl_monitor *mon, unsigned int state, unsigned long *next) +{ + bool pagefault = test_bit(LTL_PAGEFAULT, mon->atoms); + bool val3 = !pagefault; + bool rt = test_bit(LTL_RT, mon->atoms); + bool val1 = !rt; + bool val4 = val1 || val3; + + switch (state) { + case S0: + if (val4) + __set_bit(S0, next); + break; + } +} diff --git a/kernel/trace/rv/monitors/pagefault/pagefault_trace.h b/kernel/trace/rv/monitors/pagefault/pagefault_trace.h new file mode 100644 index 000000000000..fe1f82597b1a --- /dev/null +++ b/kernel/trace/rv/monitors/pagefault/pagefault_trace.h @@ -0,0 +1,14 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* + * Snippet to be included in rv_trace.h + */ + +#ifdef CONFIG_RV_MON_PAGEFAULT +DEFINE_EVENT(event_ltl_monitor_id, event_pagefault, + TP_PROTO(struct task_struct *task, char *states, char *atoms, char *next), + TP_ARGS(task, states, atoms, next)); +DEFINE_EVENT(error_ltl_monitor_id, error_pagefault, + TP_PROTO(struct task_struct *task), + TP_ARGS(task)); +#endif /* CONFIG_RV_MON_PAGEFAULT */ diff --git a/kernel/trace/rv/rv_trace.h b/kernel/trace/rv/rv_trace.h index f9fb848bae91..02c906c9745b 100644 --- a/kernel/trace/rv/rv_trace.h +++ b/kernel/trace/rv/rv_trace.h @@ -172,6 +172,7 @@ TRACE_EVENT(error_ltl_monitor_id, TP_printk("%s[%d]: violation detected", __get_str(comm), __entry->pid) ); +#include // Add new monitors based on CONFIG_LTL_MON_EVENTS_ID here #endif /* CONFIG_LTL_MON_EVENTS_ID */ #endif /* _TRACE_RV_H */ diff --git a/tools/verification/models/rtapp/pagefault.ltl b/tools/verification/models/rtapp/pagefault.ltl new file mode 100644 index 000000000000..d7ce62102733 --- /dev/null +++ b/tools/verification/models/rtapp/pagefault.ltl @@ -0,0 +1 @@ +RULE = always (RT imply not PAGEFAULT)