From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.3 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D2FACC4724C for ; Fri, 1 May 2020 04:36:13 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 7E1862071C for ; Fri, 1 May 2020 04:36:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="XMv8NsRe" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7E1862071C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 49CzwB2h1kzDrBp for ; Fri, 1 May 2020 14:36:10 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=gmail.com (client-ip=2607:f8b0:4864:20::644; helo=mail-pl1-x644.google.com; envelope-from=jniethe5@gmail.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20161025 header.b=XMv8NsRe; dkim-atps=neutral Received: from mail-pl1-x644.google.com (mail-pl1-x644.google.com [IPv6:2607:f8b0:4864:20::644]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 49Cyvc16V5zDr9C for ; Fri, 1 May 2020 13:50:35 +1000 (AEST) Received: by mail-pl1-x644.google.com with SMTP id t16so3236754plo.7 for ; Thu, 30 Apr 2020 20:50:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=HR2Q93IHFamm/+Rq2dVc3rw6swQ2uyQgFr6tB0PO+vc=; b=XMv8NsRexbi1QXhO94pXZAX3y6cOhqEhrsbA2jNvfyR336seTip5CbOsGdtPpjVvdd +dlayLLklMEluJu5t8NYenva0o9I/tWa2RK1G45nxi/fW53cPDHNQCKuGVjYw2NZ5ldR dbhzkB4Eq15+8NheZouJFWiiEjG/tub3Ib8bOPU0694Y3PjeWRMAKJL1x1HXVDhrc9s8 68M8H6+eN0njZXLcW/vtAUn8M3WBfSu5SM2ORJkC9ueT/P3vTI5TqClOrZsouCz+Da3z tqXQjvskMJDChPo0ci3O0sC8JmwIYWO6079VtWf8lpTjrlOrJVoKVlQVP9WzAzaEUHVS a8NQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=HR2Q93IHFamm/+Rq2dVc3rw6swQ2uyQgFr6tB0PO+vc=; b=en8a8Ug/TW+EYc+LiCpka6ISwQGo8gQ799sBHJqfbJsBrGNwrLHXRDf9Nr1dYrZPuK cN4FYvkQ3yxKymKBmujnElW5zFQGxNnOrdK7NDowTNKz5IlYFA/s3T/W/HbUJUD6kCP4 DZXT+U17uTEsI3d3gdzdhTO8luQv4wIIRKn0fmh1lYDvNAqKJPhqzjf+0eWx33SnZ7Ou JSDd3IyHGv0r25eTaqibpQQ5akfdIQj8uertctu1TEd7wRQvy/rQaHbhOslNfjaayu/E pZcZp/OUlR7HKV9R1zGTE9Ps9kwk2QPUQ4f3QL/OKuoIeQ9dTyGA6foct5dWYyZAMo3V bQlA== X-Gm-Message-State: AGi0PuZDh1ttlCEc+WVm/uiSXAvNDVj/jh5Gcd3RlJNB5EvG7kmxjrHd VlauAmscAuEKcurGpG8f7sXlE/O0pdVyuQ== X-Google-Smtp-Source: APiQypIob41UGzZWVrv9Y0r6zet7jU/uOpc+5OhXVFEpJED5nY7sLc0fZeNUObWMFE1SWHkcy7VEnA== X-Received: by 2002:a17:90a:a484:: with SMTP id z4mr2359952pjp.40.1588305033798; Thu, 30 Apr 2020 20:50:33 -0700 (PDT) Received: from localhost.localdomain (180-150-65-4.b49641.syd.nbn.aussiebb.net. [180.150.65.4]) by smtp.gmail.com with ESMTPSA id w28sm940082pgc.26.2020.04.30.20.50.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 30 Apr 2020 20:50:33 -0700 (PDT) From: Jordan Niethe To: linuxppc-dev@lists.ozlabs.org Subject: [PATCH v7 26/28] powerpc: Support prefixed instructions in alignment handler Date: Fri, 1 May 2020 13:42:18 +1000 Message-Id: <20200501034220.8982-27-jniethe5@gmail.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200501034220.8982-1-jniethe5@gmail.com> References: <20200501034220.8982-1-jniethe5@gmail.com> X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: alistair@popple.id.au, npiggin@gmail.com, bala24@linux.ibm.com, naveen.n.rao@linux.vnet.ibm.com, Jordan Niethe , dja@axtens.net Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" If a prefixed instruction results in an alignment exception, the SRR1_PREFIXED bit is set. The handler attempts to emulate the responsible instruction and then increment the NIP past it. Use SRR1_PREFIXED to determine by how much the NIP should be incremented. Prefixed instructions are not permitted to cross 64-byte boundaries. If they do the alignment interrupt is invoked with SRR1 BOUNDARY bit set. If this occurs send a SIGBUS to the offending process if in user mode. If in kernel mode call bad_page_fault(). Signed-off-by: Jordan Niethe --- v2: - Move __get_user_instr() and __get_user_instr_inatomic() to this commit (previously in "powerpc sstep: Prepare to support prefixed instructions"). - Rename sufx to suffix - Use a macro for calculating instruction length v3: Move __get_user_{instr(), instr_inatomic()} up with the other get_user definitions and remove nested if. v4: Rolled into "Add prefixed instructions to instruction data type" v5: Only one definition of inst_length() --- arch/powerpc/kernel/traps.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 493a3fa0ac1a..105242cc2f28 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -583,6 +583,8 @@ static inline int check_io_access(struct pt_regs *regs) #define REASON_ILLEGAL (ESR_PIL | ESR_PUO) #define REASON_PRIVILEGED ESR_PPR #define REASON_TRAP ESR_PTR +#define REASON_PREFIXED 0 +#define REASON_BOUNDARY 0 /* single-step stuff */ #define single_stepping(regs) (current->thread.debug.dbcr0 & DBCR0_IC) @@ -597,12 +599,16 @@ static inline int check_io_access(struct pt_regs *regs) #define REASON_ILLEGAL SRR1_PROGILL #define REASON_PRIVILEGED SRR1_PROGPRIV #define REASON_TRAP SRR1_PROGTRAP +#define REASON_PREFIXED SRR1_PREFIXED +#define REASON_BOUNDARY SRR1_BOUNDARY #define single_stepping(regs) ((regs)->msr & MSR_SE) #define clear_single_step(regs) ((regs)->msr &= ~MSR_SE) #define clear_br_trace(regs) ((regs)->msr &= ~MSR_BE) #endif +#define inst_length(reason) (((reason) & REASON_PREFIXED) ? 8 : 4) + #if defined(CONFIG_E500) int machine_check_e500mc(struct pt_regs *regs) { @@ -1593,11 +1599,20 @@ void alignment_exception(struct pt_regs *regs) { enum ctx_state prev_state = exception_enter(); int sig, code, fixed = 0; + unsigned long reason; /* We restore the interrupt state now */ if (!arch_irq_disabled_regs(regs)) local_irq_enable(); + reason = get_reason(regs); + + if (reason & REASON_BOUNDARY) { + sig = SIGBUS; + code = BUS_ADRALN; + goto bad; + } + if (tm_abort_check(regs, TM_CAUSE_ALIGNMENT | TM_CAUSE_PERSISTENT)) goto bail; @@ -1606,7 +1621,8 @@ void alignment_exception(struct pt_regs *regs) fixed = fix_alignment(regs); if (fixed == 1) { - regs->nip += 4; /* skip over emulated instruction */ + /* skip over emulated instruction */ + regs->nip += inst_length(reason); emulate_single_step(regs); goto bail; } @@ -1619,6 +1635,7 @@ void alignment_exception(struct pt_regs *regs) sig = SIGBUS; code = BUS_ADRALN; } +bad: if (user_mode(regs)) _exception(sig, regs, code, regs->dar); else -- 2.17.1