From patchwork Mon Jan 21 15:33:27 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julien Thierry X-Patchwork-Id: 10774015 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C9E636C2 for ; Mon, 21 Jan 2019 15:37:35 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B814B29D45 for ; Mon, 21 Jan 2019 15:37:35 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id ABC362A37F; Mon, 21 Jan 2019 15:37:35 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 2DF3F29D45 for ; Mon, 21 Jan 2019 15:37:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=NX+3VAqo4L/+oZUnZn2Pm8bdTDOnXg1rIuIDzxHA2Ng=; b=hkcAb3z56RWPl2Hcs6GWUFXTGY X/NQgAw1AnTxi3pTNh8oDESgpqmmcsJ+uZqkVT/aENwtxoUZMA/woZD/Rw+WiJVTnPvTUrCGVxGey qKDiiermzlD8K6cWiXnQMv/r8VtwJqZ8gloZbRf1nIq2ls8+NT5h4k8+wSBss87dHVdRbT4n+43lt wJZFjB9eQZNz1ZYrAOojp30b/LkW8xNZ6q56mFK7c/kbQr+ELxvgaOJyfC9zzwfHilolsQkH40gYe RmZtgL08ATPfHKWX9AJXPiGU9k4x+NVFFyqHyRDksBv/HIVhqchfWxJFgHaaWFtKluewkAUtIfLUg nEJNOItQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1glbdj-00014C-Jx; Mon, 21 Jan 2019 15:37:31 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1glbae-0005WG-SA for linux-arm-kernel@lists.infradead.org; Mon, 21 Jan 2019 15:34:33 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id E051E1688; Mon, 21 Jan 2019 07:34:19 -0800 (PST) Received: from e112298-lin.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id A90B73F5C1; Mon, 21 Jan 2019 07:34:17 -0800 (PST) From: Julien Thierry To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v9 08/26] arm64: Make PMR part of task context Date: Mon, 21 Jan 2019 15:33:27 +0000 Message-Id: <1548084825-8803-9-git-send-email-julien.thierry@arm.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1548084825-8803-1-git-send-email-julien.thierry@arm.com> References: <1548084825-8803-1-git-send-email-julien.thierry@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190121_073421_589366_D371D788 X-CRM114-Status: GOOD ( 13.45 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mark.rutland@arm.com, daniel.thompson@linaro.org, Julien Thierry , marc.zyngier@arm.com, catalin.marinas@arm.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, christoffer.dall@arm.com, james.morse@arm.com, Oleg Nesterov , joel@joelfernandes.org, Dave Martin MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP In order to replace PSR.I interrupt disabling/enabling with ICC_PMR_EL1 interrupt masking, ICC_PMR_EL1 needs to be saved/restored when taking/returning from an exception. This mimics the way hardware saves and restores PSR.I bit in spsr_el1 for exceptions and ERET. Add PMR to the registers to save in the pt_regs struct upon kernel entry, and restore it before ERET. Also, initialize it to a sane value when creating new tasks. Signed-off-by: Julien Thierry Reviewed-by: Catalin Marinas Cc: Catalin Marinas Cc: Will Deacon Cc: Oleg Nesterov Cc: Dave Martin Reviewed-by: Marc Zyngier --- arch/arm64/include/asm/processor.h | 3 +++ arch/arm64/include/asm/ptrace.h | 14 +++++++++++--- arch/arm64/kernel/asm-offsets.c | 1 + arch/arm64/kernel/entry.S | 14 ++++++++++++++ arch/arm64/kernel/process.c | 6 ++++++ 5 files changed, 35 insertions(+), 3 deletions(-) diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h index f1a7ab1..5d9ce62 100644 --- a/arch/arm64/include/asm/processor.h +++ b/arch/arm64/include/asm/processor.h @@ -191,6 +191,9 @@ static inline void start_thread_common(struct pt_regs *regs, unsigned long pc) memset(regs, 0, sizeof(*regs)); forget_syscall(regs); regs->pc = pc; + + if (system_uses_irq_prio_masking()) + regs->pmr_save = GIC_PRIO_IRQON; } static inline void start_thread(struct pt_regs *regs, unsigned long pc, diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h index 05cf913..43e5df5 100644 --- a/arch/arm64/include/asm/ptrace.h +++ b/arch/arm64/include/asm/ptrace.h @@ -19,6 +19,8 @@ #ifndef __ASM_PTRACE_H #define __ASM_PTRACE_H +#include + #include /* Current Exception Level values, as contained in CurrentEL */ @@ -179,7 +181,8 @@ struct pt_regs { #endif u64 orig_addr_limit; - u64 unused; // maintain 16 byte alignment + /* Only valid when ARM64_HAS_IRQ_PRIO_MASKING is enabled. */ + u64 pmr_save; u64 stackframe[2]; }; @@ -214,8 +217,13 @@ static inline void forget_syscall(struct pt_regs *regs) #define processor_mode(regs) \ ((regs)->pstate & PSR_MODE_MASK) -#define interrupts_enabled(regs) \ - (!((regs)->pstate & PSR_I_BIT)) +#define irqs_priority_unmasked(regs) \ + (system_uses_irq_prio_masking() ? \ + (regs)->pmr_save == GIC_PRIO_IRQON : \ + true) + +#define interrupts_enabled(regs) \ + (!((regs)->pstate & PSR_I_BIT) && irqs_priority_unmasked(regs)) #define fast_interrupts_enabled(regs) \ (!((regs)->pstate & PSR_F_BIT)) diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c index 65b8afc..90ab2cf 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -81,6 +81,7 @@ int main(void) DEFINE(S_ORIG_X0, offsetof(struct pt_regs, orig_x0)); DEFINE(S_SYSCALLNO, offsetof(struct pt_regs, syscallno)); DEFINE(S_ORIG_ADDR_LIMIT, offsetof(struct pt_regs, orig_addr_limit)); + DEFINE(S_PMR_SAVE, offsetof(struct pt_regs, pmr_save)); DEFINE(S_STACKFRAME, offsetof(struct pt_regs, stackframe)); DEFINE(S_FRAME_SIZE, sizeof(struct pt_regs)); BLANK(); diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index 0ec0c46..35a47f6 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -249,6 +249,12 @@ alternative_else_nop_endif msr sp_el0, tsk .endif + /* Save pmr */ +alternative_if ARM64_HAS_IRQ_PRIO_MASKING + mrs_s x20, SYS_ICC_PMR_EL1 + str x20, [sp, #S_PMR_SAVE] +alternative_else_nop_endif + /* * Registers that may be useful after this macro is invoked: * @@ -269,6 +275,14 @@ alternative_else_nop_endif /* No need to restore UAO, it will be restored from SPSR_EL1 */ .endif + /* Restore pmr */ +alternative_if ARM64_HAS_IRQ_PRIO_MASKING + ldr x20, [sp, #S_PMR_SAVE] + msr_s SYS_ICC_PMR_EL1, x20 + /* Ensure priority change is seen by redistributor */ + dsb sy +alternative_else_nop_endif + ldp x21, x22, [sp, #S_PC] // load ELR, SPSR .if \el == 0 ct_user_enter diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index a0f985a..6d410fc 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -232,6 +232,9 @@ void __show_regs(struct pt_regs *regs) printk("sp : %016llx\n", sp); + if (system_uses_irq_prio_masking()) + printk("pmr_save: %08llx\n", regs->pmr_save); + i = top_reg; while (i >= 0) { @@ -363,6 +366,9 @@ int copy_thread(unsigned long clone_flags, unsigned long stack_start, if (arm64_get_ssbd_state() == ARM64_SSBD_FORCE_DISABLE) childregs->pstate |= PSR_SSBS_BIT; + if (system_uses_irq_prio_masking()) + childregs->pmr_save = GIC_PRIO_IRQON; + p->thread.cpu_context.x19 = stack_start; p->thread.cpu_context.x20 = stk_sz; }