From patchwork Fri Oct 9 19:42:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ira Weiny X-Patchwork-Id: 11827217 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 098751744 for ; Fri, 9 Oct 2020 19:43:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E60DC222BA for ; Fri, 9 Oct 2020 19:43:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2403792AbgJITn0 (ORCPT ); Fri, 9 Oct 2020 15:43:26 -0400 Received: from mga01.intel.com ([192.55.52.88]:2891 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2403780AbgJITnW (ORCPT ); Fri, 9 Oct 2020 15:43:22 -0400 IronPort-SDR: h0uS+odjFhrLMbeHBMREWtH27f8f0AK+9++50O07wCMAt7OG3hwBG+6xlumEP2lmNkr8CS8nCb JhIUM6SiNBMQ== X-IronPort-AV: E=McAfee;i="6000,8403,9769"; a="182975359" X-IronPort-AV: E=Sophos;i="5.77,355,1596524400"; d="scan'208";a="182975359" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Oct 2020 12:43:22 -0700 IronPort-SDR: MkfnCLSSRwOBTQEfWdMVmXruOqSNup+ZdyDI/59QanK2/5c7cgi3y+Kyqitw3PbH47IJQ1/95p LM+Wp9uIp/MA== X-IronPort-AV: E=Sophos;i="5.77,355,1596524400"; d="scan'208";a="354957039" Received: from iweiny-desk2.sc.intel.com (HELO localhost) ([10.3.52.147]) by fmsmga003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Oct 2020 12:43:21 -0700 From: ira.weiny@intel.com To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Andy Lutomirski , Peter Zijlstra Cc: Ira Weiny , x86@kernel.org, Dave Hansen , Dan Williams , Andrew Morton , Fenghua Yu , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-nvdimm@lists.01.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org Subject: [PATCH RFC V3 6/9] x86/entry: Pass irqentry_state_t by reference Date: Fri, 9 Oct 2020 12:42:55 -0700 Message-Id: <20201009194258.3207172-7-ira.weiny@intel.com> X-Mailer: git-send-email 2.28.0.rc0.12.gb6a658bd00c9 In-Reply-To: <20201009194258.3207172-1-ira.weiny@intel.com> References: <20201009194258.3207172-1-ira.weiny@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org From: Ira Weiny In preparation for adding PKS information to struct irqentry_state_t change all call sites and usages to pass the struct by reference instead of by value. Signed-off-by: Ira Weiny Signed-off-by: Thomas Gleixner --- arch/x86/entry/common.c | 16 +++++++--------- arch/x86/include/asm/idtentry.h | 29 +++++++++++++++++------------ arch/x86/kernel/kvm.c | 4 ++-- arch/x86/kernel/nmi.c | 7 ++++--- arch/x86/kernel/traps.c | 21 +++++++++++++-------- arch/x86/mm/fault.c | 4 ++-- include/linux/entry-common.h | 7 ++++--- kernel/entry/common.c | 20 ++++++++------------ 8 files changed, 57 insertions(+), 51 deletions(-) diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c index 870efeec8bda..305da13770b6 100644 --- a/arch/x86/entry/common.c +++ b/arch/x86/entry/common.c @@ -209,9 +209,9 @@ SYSCALL_DEFINE0(ni_syscall) return -ENOSYS; } -noinstr bool idtentry_enter_nmi(struct pt_regs *regs) +noinstr void idtentry_enter_nmi(struct pt_regs *regs, irqentry_state_t *irq_state) { - bool irq_state = lockdep_hardirqs_enabled(); + irq_state->exit_rcu = lockdep_hardirqs_enabled(); __nmi_enter(); lockdep_hardirqs_off(CALLER_ADDR0); @@ -222,15 +222,13 @@ noinstr bool idtentry_enter_nmi(struct pt_regs *regs) trace_hardirqs_off_finish(); ftrace_nmi_enter(); instrumentation_end(); - - return irq_state; } -noinstr void idtentry_exit_nmi(struct pt_regs *regs, bool restore) +noinstr void idtentry_exit_nmi(struct pt_regs *regs, irqentry_state_t *irq_state) { instrumentation_begin(); ftrace_nmi_exit(); - if (restore) { + if (irq_state->exit_rcu) { trace_hardirqs_on_prepare(); lockdep_hardirqs_on_prepare(CALLER_ADDR0); } @@ -238,7 +236,7 @@ noinstr void idtentry_exit_nmi(struct pt_regs *regs, bool restore) rcu_nmi_exit(); lockdep_hardirq_exit(); - if (restore) + if (irq_state->exit_rcu) lockdep_hardirqs_on(CALLER_ADDR0); __nmi_exit(); } @@ -295,7 +293,7 @@ __visible noinstr void xen_pv_evtchn_do_upcall(struct pt_regs *regs) bool inhcall; irqentry_state_t state; - state = irqentry_enter(regs); + irqentry_enter(regs, &state); old_regs = set_irq_regs(regs); instrumentation_begin(); @@ -311,7 +309,7 @@ __visible noinstr void xen_pv_evtchn_do_upcall(struct pt_regs *regs) instrumentation_end(); restore_inhcall(inhcall); } else { - irqentry_exit(regs, state); + irqentry_exit(regs, &state); } } #endif /* CONFIG_XEN_PV */ diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h index a0638640f1ed..622889ba21d0 100644 --- a/arch/x86/include/asm/idtentry.h +++ b/arch/x86/include/asm/idtentry.h @@ -11,8 +11,8 @@ #include -bool idtentry_enter_nmi(struct pt_regs *regs); -void idtentry_exit_nmi(struct pt_regs *regs, bool irq_state); +void idtentry_enter_nmi(struct pt_regs *regs, irqentry_state_t *irq_state); +void idtentry_exit_nmi(struct pt_regs *regs, irqentry_state_t *irq_state); /** * DECLARE_IDTENTRY - Declare functions for simple IDT entry points @@ -52,12 +52,13 @@ static __always_inline void __##func(struct pt_regs *regs); \ \ __visible noinstr void func(struct pt_regs *regs) \ { \ - irqentry_state_t state = irqentry_enter(regs); \ + irqentry_state_t state; \ \ + irqentry_enter(regs, &state); \ instrumentation_begin(); \ __##func (regs); \ instrumentation_end(); \ - irqentry_exit(regs, state); \ + irqentry_exit(regs, &state); \ } \ \ static __always_inline void __##func(struct pt_regs *regs) @@ -99,12 +100,13 @@ static __always_inline void __##func(struct pt_regs *regs, \ __visible noinstr void func(struct pt_regs *regs, \ unsigned long error_code) \ { \ - irqentry_state_t state = irqentry_enter(regs); \ + irqentry_state_t state; \ \ + irqentry_enter(regs, &state); \ instrumentation_begin(); \ __##func (regs, error_code); \ instrumentation_end(); \ - irqentry_exit(regs, state); \ + irqentry_exit(regs, &state); \ } \ \ static __always_inline void __##func(struct pt_regs *regs, \ @@ -195,15 +197,16 @@ static __always_inline void __##func(struct pt_regs *regs, u8 vector); \ __visible noinstr void func(struct pt_regs *regs, \ unsigned long error_code) \ { \ - irqentry_state_t state = irqentry_enter(regs); \ + irqentry_state_t state; \ \ + irqentry_enter(regs, &state); \ instrumentation_begin(); \ irq_enter_rcu(); \ kvm_set_cpu_l1tf_flush_l1d(); \ __##func (regs, (u8)error_code); \ irq_exit_rcu(); \ instrumentation_end(); \ - irqentry_exit(regs, state); \ + irqentry_exit(regs, &state); \ } \ \ static __always_inline void __##func(struct pt_regs *regs, u8 vector) @@ -237,15 +240,16 @@ static void __##func(struct pt_regs *regs); \ \ __visible noinstr void func(struct pt_regs *regs) \ { \ - irqentry_state_t state = irqentry_enter(regs); \ + irqentry_state_t state; \ \ + irqentry_enter(regs, &state); \ instrumentation_begin(); \ irq_enter_rcu(); \ kvm_set_cpu_l1tf_flush_l1d(); \ run_sysvec_on_irqstack_cond(__##func, regs); \ irq_exit_rcu(); \ instrumentation_end(); \ - irqentry_exit(regs, state); \ + irqentry_exit(regs, &state); \ } \ \ static noinline void __##func(struct pt_regs *regs) @@ -266,15 +270,16 @@ static __always_inline void __##func(struct pt_regs *regs); \ \ __visible noinstr void func(struct pt_regs *regs) \ { \ - irqentry_state_t state = irqentry_enter(regs); \ + irqentry_state_t state; \ \ + irqentry_enter(regs, &state); \ instrumentation_begin(); \ __irq_enter_raw(); \ kvm_set_cpu_l1tf_flush_l1d(); \ __##func (regs); \ __irq_exit_raw(); \ instrumentation_end(); \ - irqentry_exit(regs, state); \ + irqentry_exit(regs, &state); \ } \ \ static __always_inline void __##func(struct pt_regs *regs) diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 9663ba31347c..c6be0a54236f 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -241,7 +241,7 @@ noinstr bool __kvm_handle_async_pf(struct pt_regs *regs, u32 token) if (!flags) return false; - state = irqentry_enter(regs); + irqentry_enter(regs, &state); instrumentation_begin(); /* @@ -262,7 +262,7 @@ noinstr bool __kvm_handle_async_pf(struct pt_regs *regs, u32 token) } instrumentation_end(); - irqentry_exit(regs, state); + irqentry_exit(regs, &state); return true; } diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c index 4fc9954a9560..68c07cad0150 100644 --- a/arch/x86/kernel/nmi.c +++ b/arch/x86/kernel/nmi.c @@ -33,6 +33,7 @@ #include #include #include +#include #define CREATE_TRACE_POINTS #include @@ -475,7 +476,7 @@ static DEFINE_PER_CPU(unsigned long, nmi_dr7); DEFINE_IDTENTRY_RAW(exc_nmi) { - bool irq_state; + irqentry_state_t irq_state = { }; if (IS_ENABLED(CONFIG_SMP) && arch_cpu_is_offline(smp_processor_id())) return; @@ -490,14 +491,14 @@ DEFINE_IDTENTRY_RAW(exc_nmi) this_cpu_write(nmi_dr7, local_db_save()); - irq_state = idtentry_enter_nmi(regs); + idtentry_enter_nmi(regs, &irq_state); inc_irq_stat(__nmi_count); if (!ignore_nmis) default_do_nmi(regs); - idtentry_exit_nmi(regs, irq_state); + idtentry_exit_nmi(regs, &irq_state); local_db_restore(this_cpu_read(nmi_dr7)); diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 81a2fb711091..daf7bc02fc99 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -254,11 +254,11 @@ DEFINE_IDTENTRY_RAW(exc_invalid_op) if (!user_mode(regs) && handle_bug(regs)) return; - state = irqentry_enter(regs); + irqentry_enter(regs, &state); instrumentation_begin(); handle_invalid_op(regs); instrumentation_end(); - irqentry_exit(regs, state); + irqentry_exit(regs, &state); } DEFINE_IDTENTRY(exc_coproc_segment_overrun) @@ -342,6 +342,7 @@ __visible void __noreturn handle_stack_overflow(const char *message, */ DEFINE_IDTENTRY_DF(exc_double_fault) { + irqentry_state_t irq_state; static const char str[] = "double fault"; struct task_struct *tsk = current; @@ -404,7 +405,7 @@ DEFINE_IDTENTRY_DF(exc_double_fault) } #endif - idtentry_enter_nmi(regs); + idtentry_enter_nmi(regs, &irq_state); instrumentation_begin(); notify_die(DIE_TRAP, str, regs, error_code, X86_TRAP_DF, SIGSEGV); @@ -650,12 +651,15 @@ DEFINE_IDTENTRY_RAW(exc_int3) instrumentation_end(); irqentry_exit_to_user_mode(regs); } else { - bool irq_state = idtentry_enter_nmi(regs); + irqentry_state_t irq_state; + + idtentry_enter_nmi(regs, &irq_state); + instrumentation_begin(); if (!do_int3(regs)) die("int3", regs, 0); instrumentation_end(); - idtentry_exit_nmi(regs, irq_state); + idtentry_exit_nmi(regs, &irq_state); } } @@ -861,7 +865,9 @@ static __always_inline void exc_debug_kernel(struct pt_regs *regs, * includes the entry stack is excluded for everything. */ unsigned long dr7 = local_db_save(); - bool irq_state = idtentry_enter_nmi(regs); + irqentry_state_t irq_state; + + idtentry_enter_nmi(regs, &irq_state); instrumentation_begin(); /* @@ -880,8 +886,7 @@ static __always_inline void exc_debug_kernel(struct pt_regs *regs, handle_debug(regs, dr6, false); instrumentation_end(); - idtentry_exit_nmi(regs, irq_state); - + idtentry_exit_nmi(regs, &irq_state); local_db_restore(dr7); } diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 6e3e8a124903..e55bc4bff389 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -1476,11 +1476,11 @@ DEFINE_IDTENTRY_RAW_ERRORCODE(exc_page_fault) * code reenabled RCU to avoid subsequent wreckage which helps * debugability. */ - state = irqentry_enter(regs); + irqentry_enter(regs, &state); instrumentation_begin(); handle_page_fault(regs, error_code, address); instrumentation_end(); - irqentry_exit(regs, state); + irqentry_exit(regs, &state); } diff --git a/include/linux/entry-common.h b/include/linux/entry-common.h index 159c7476b11b..de4f24c554ee 100644 --- a/include/linux/entry-common.h +++ b/include/linux/entry-common.h @@ -349,6 +349,7 @@ typedef struct irqentry_state { /** * irqentry_enter - Handle state tracking on ordinary interrupt entries * @regs: Pointer to pt_regs of interrupted context + * @state: Pointer to an object to store the irq state * * Invokes: * - lockdep irqflag state tracking as low level ASM entry disabled @@ -377,7 +378,7 @@ typedef struct irqentry_state { * * Returns: An opaque object that must be passed to idtentry_exit() */ -irqentry_state_t noinstr irqentry_enter(struct pt_regs *regs); +void noinstr irqentry_enter(struct pt_regs *regs, irqentry_state_t *state); /** * irqentry_exit_cond_resched - Conditionally reschedule on return from interrupt @@ -389,7 +390,7 @@ void irqentry_exit_cond_resched(void); /** * irqentry_exit - Handle return from exception that used irqentry_enter() * @regs: Pointer to pt_regs (exception entry regs) - * @state: Return value from matching call to irqentry_enter() + * @state: Reference to the value saved in irqentry_enter() * * Depending on the return target (kernel/user) this runs the necessary * preemption and work checks if possible and reguired and returns to @@ -400,6 +401,6 @@ void irqentry_exit_cond_resched(void); * * Counterpart to irqentry_enter(). */ -void noinstr irqentry_exit(struct pt_regs *regs, irqentry_state_t state); +void noinstr irqentry_exit(struct pt_regs *regs, irqentry_state_t *state); #endif diff --git a/kernel/entry/common.c b/kernel/entry/common.c index 6fdb6105e6d6..21601993ad1b 100644 --- a/kernel/entry/common.c +++ b/kernel/entry/common.c @@ -282,15 +282,13 @@ noinstr void irqentry_exit_to_user_mode(struct pt_regs *regs) exit_to_user_mode(); } -noinstr irqentry_state_t irqentry_enter(struct pt_regs *regs) +noinstr void irqentry_enter(struct pt_regs *regs, irqentry_state_t *state) { - irqentry_state_t ret = { - .exit_rcu = false, - }; + state->exit_rcu = false; if (user_mode(regs)) { irqentry_enter_from_user_mode(regs); - return ret; + return; } /* @@ -328,8 +326,8 @@ noinstr irqentry_state_t irqentry_enter(struct pt_regs *regs) trace_hardirqs_off_finish(); instrumentation_end(); - ret.exit_rcu = true; - return ret; + state->exit_rcu = true; + return; } /* @@ -343,8 +341,6 @@ noinstr irqentry_state_t irqentry_enter(struct pt_regs *regs) /* Use the combo lockdep/tracing function */ trace_hardirqs_off(); instrumentation_end(); - - return ret; } void irqentry_exit_cond_resched(void) @@ -359,7 +355,7 @@ void irqentry_exit_cond_resched(void) } } -noinstr void irqentry_exit(struct pt_regs *regs, irqentry_state_t state) +noinstr void irqentry_exit(struct pt_regs *regs, irqentry_state_t *state) { lockdep_assert_irqs_disabled(); @@ -372,7 +368,7 @@ noinstr void irqentry_exit(struct pt_regs *regs, irqentry_state_t state) * carefully and needs the same ordering of lockdep/tracing * and RCU as the return to user mode path. */ - if (state.exit_rcu) { + if (state->exit_rcu) { instrumentation_begin(); /* Tell the tracer that IRET will enable interrupts */ trace_hardirqs_on_prepare(); @@ -394,7 +390,7 @@ noinstr void irqentry_exit(struct pt_regs *regs, irqentry_state_t state) * IRQ flags state is correct already. Just tell RCU if it * was not watching on entry. */ - if (state.exit_rcu) + if (state->exit_rcu) rcu_irq_exit(); } }