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,URIBL_BLOCKED,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 9BA89C28CBC for ; Wed, 6 May 2020 04:06:49 +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 1510D20752 for ; Wed, 6 May 2020 04:06:49 +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="VKODNlez" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1510D20752 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 49H31y50YlzDrBk for ; Wed, 6 May 2020 14:06:46 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=gmail.com (client-ip=2607:f8b0:4864:20::1041; helo=mail-pj1-x1041.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=VKODNlez; dkim-atps=neutral Received: from mail-pj1-x1041.google.com (mail-pj1-x1041.google.com [IPv6:2607:f8b0:4864:20::1041]) (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 49H2YH0qZ9zDqSs for ; Wed, 6 May 2020 13:45:22 +1000 (AEST) Received: by mail-pj1-x1041.google.com with SMTP id mq3so209997pjb.1 for ; Tue, 05 May 2020 20:45:22 -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=XlnyX3p3wIbi+WXoKT5FBUL5eyYJzAnThO2alVa7NHw=; b=VKODNlezkPSBfvfLsAYxMdI+2sj2AED9+A8yrURdLon75VjAt+xxpaFVYQ4qZJc2BD xZP0qYKwtfB2ICX29YAaVV4yHAl0Mjj0gT2ZZRh3Fv91QgGAH2ii/DehjIEzX06TBM5N bASxXAMoby/e7H3COJFfF1oWGOi78w1yWCTT+iB4XLYrxQLUahAWMTbUo37dYbjR0Adp Y4EvkpgDY5v4y/TNljXUS0841qgHYcHRWcVIT7evU2VHPKezvACct79G/njfXKeThR+9 XGA+DmZVGqeLKVRnh+gSjXt5PB9PHwMhjrkKHMgN596l4PbH0mqEh21dWDtMOmoQoTDy K2Xg== 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=XlnyX3p3wIbi+WXoKT5FBUL5eyYJzAnThO2alVa7NHw=; b=B8hG2mrb20Y2vjunkD8zF1n2mHur6PbAtGV506ucbVzL+MxJ0E+7Wh3A5PiFzV2Hdy /ZBwMWFuHB1KZOmLj0RZjWE+nUjZmwRnKSNVWvNneuZ7tbQtc66M3T+Mh4RgLFIbOd0N 7RBkMn2mcO8iEoLJ0gbw1HPyYzHo0pUmMNsYet5RstS3IqcChGpZIlsgQDht/YBonS5Z hgFzYxL3SPQBrYDaLLDuW52qhszqiATSHy3oTUrUSqOQgrFJSz23W1NK8pqFB1ctgtyq L/X81C+UaK9iWwFm4lKrfWFhyu10TEoDZSlvWqETEnWtaex2P+ySwvC2eAXRJBknXeof uzig== X-Gm-Message-State: AGi0PuZ+n5MtaBuQjgxBHkpo7onrDNmNcX/GKLIilETfiavJgB9P0AwU NQnMbJK5AbOcRzzd1b6XE32mxngwEOx32w== X-Google-Smtp-Source: APiQypI6o+DWjRsiijtppwG2Bcw+vfh/sD1Ix1VeYhy4FvQp7MKQkyyc10gFBDePxkZCIPprTUmxlQ== X-Received: by 2002:a17:90a:33c5:: with SMTP id n63mr6649738pjb.4.1588736720161; Tue, 05 May 2020 20:45:20 -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 k4sm465676pgg.88.2020.05.05.20.45.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 05 May 2020 20:45:19 -0700 (PDT) From: Jordan Niethe To: linuxppc-dev@lists.ozlabs.org Subject: [PATCH v8 12/30] powerpc: Use a function for reading instructions Date: Wed, 6 May 2020 13:40:32 +1000 Message-Id: <20200506034050.24806-13-jniethe5@gmail.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200506034050.24806-1-jniethe5@gmail.com> References: <20200506034050.24806-1-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" Prefixed instructions will mean there are instructions of different length. As a result dereferencing a pointer to an instruction will not necessarily give the desired result. Introduce a function for reading instructions from memory into the instruction data type. Reviewed-by: Alistair Popple Signed-off-by: Jordan Niethe --- v4: New to series v5: - Rename read_inst() -> probe_kernel_read_inst() - No longer modify uprobe probe type in this patch v6: - feature-fixups.c: do_final_fixups(): Use here - arch_prepare_kprobe(): patch_instruction(): no longer part of this patch - Move probe_kernel_read_inst() out of this patch - Use in uprobes v8: style --- arch/powerpc/include/asm/inst.h | 5 +++++ arch/powerpc/kernel/kprobes.c | 6 +++--- arch/powerpc/kernel/mce_power.c | 2 +- arch/powerpc/kernel/optprobes.c | 4 ++-- arch/powerpc/kernel/trace/ftrace.c | 4 ++-- arch/powerpc/kernel/uprobes.c | 2 +- arch/powerpc/lib/code-patching.c | 26 ++++++++++++++------------ arch/powerpc/lib/feature-fixups.c | 4 ++-- arch/powerpc/xmon/xmon.c | 6 +++--- 9 files changed, 33 insertions(+), 26 deletions(-) diff --git a/arch/powerpc/include/asm/inst.h b/arch/powerpc/include/asm/inst.h index 19d8bb7a1c2b..552e953bf04f 100644 --- a/arch/powerpc/include/asm/inst.h +++ b/arch/powerpc/include/asm/inst.h @@ -27,6 +27,11 @@ static inline struct ppc_inst ppc_inst_swab(struct ppc_inst x) return ppc_inst(swab32(ppc_inst_val(x))); } +static inline struct ppc_inst ppc_inst_read(const struct ppc_inst *ptr) +{ + return *ptr; +} + static inline bool ppc_inst_equal(struct ppc_inst x, struct ppc_inst y) { return ppc_inst_val(x) == ppc_inst_val(y); diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c index a08ae5803622..f64312dca84f 100644 --- a/arch/powerpc/kernel/kprobes.c +++ b/arch/powerpc/kernel/kprobes.c @@ -106,7 +106,7 @@ kprobe_opcode_t *kprobe_lookup_name(const char *name, unsigned int offset) int arch_prepare_kprobe(struct kprobe *p) { int ret = 0; - struct ppc_inst insn = *(struct ppc_inst *)p->addr; + struct ppc_inst insn = ppc_inst_read((struct ppc_inst *)p->addr); if ((unsigned long)p->addr & 0x03) { printk("Attempt to register kprobe at an unaligned address\n"); @@ -127,7 +127,7 @@ int arch_prepare_kprobe(struct kprobe *p) if (!ret) { memcpy(p->ainsn.insn, p->addr, MAX_INSN_SIZE * sizeof(kprobe_opcode_t)); - p->opcode = *p->addr; + p->opcode = ppc_inst_val(insn); flush_icache_range((unsigned long)p->ainsn.insn, (unsigned long)p->ainsn.insn + sizeof(kprobe_opcode_t)); } @@ -217,7 +217,7 @@ NOKPROBE_SYMBOL(arch_prepare_kretprobe); static int try_to_emulate(struct kprobe *p, struct pt_regs *regs) { int ret; - struct ppc_inst insn = *(struct ppc_inst *)p->ainsn.insn; + struct ppc_inst insn = ppc_inst_read((struct ppc_inst *)p->ainsn.insn); /* regs->nip is also adjusted if emulate_step returns 1 */ ret = emulate_step(regs, insn); diff --git a/arch/powerpc/kernel/mce_power.c b/arch/powerpc/kernel/mce_power.c index cd23218c60bb..45c51ba0071b 100644 --- a/arch/powerpc/kernel/mce_power.c +++ b/arch/powerpc/kernel/mce_power.c @@ -374,7 +374,7 @@ static int mce_find_instr_ea_and_phys(struct pt_regs *regs, uint64_t *addr, pfn = addr_to_pfn(regs, regs->nip); if (pfn != ULONG_MAX) { instr_addr = (pfn << PAGE_SHIFT) + (regs->nip & ~PAGE_MASK); - instr = *(struct ppc_inst *)(instr_addr); + instr = ppc_inst_read((struct ppc_inst *)instr_addr); if (!analyse_instr(&op, &tmp, instr)) { pfn = addr_to_pfn(regs, op.ea); *addr = op.ea; diff --git a/arch/powerpc/kernel/optprobes.c b/arch/powerpc/kernel/optprobes.c index 5a71fef71c22..52c1ab3f85aa 100644 --- a/arch/powerpc/kernel/optprobes.c +++ b/arch/powerpc/kernel/optprobes.c @@ -100,9 +100,9 @@ static unsigned long can_optimize(struct kprobe *p) * Ensure that the instruction is not a conditional branch, * and that can be emulated. */ - if (!is_conditional_branch(*(struct ppc_inst *)p->ainsn.insn) && + if (!is_conditional_branch(ppc_inst_read((struct ppc_inst *)p->ainsn.insn)) && analyse_instr(&op, ®s, - *(struct ppc_inst *)p->ainsn.insn) == 1) { + ppc_inst_read((struct ppc_inst *)p->ainsn.insn)) == 1) { emulate_update_regs(®s, &op); nip = regs.nip; } diff --git a/arch/powerpc/kernel/trace/ftrace.c b/arch/powerpc/kernel/trace/ftrace.c index 3117ed675735..acd5b889815f 100644 --- a/arch/powerpc/kernel/trace/ftrace.c +++ b/arch/powerpc/kernel/trace/ftrace.c @@ -848,7 +848,7 @@ int ftrace_update_ftrace_func(ftrace_func_t func) struct ppc_inst old, new; int ret; - old = *(struct ppc_inst *)&ftrace_call; + old = ppc_inst_read((struct ppc_inst *)&ftrace_call); new = ftrace_call_replace(ip, (unsigned long)func, 1); ret = ftrace_modify_code(ip, old, new); @@ -856,7 +856,7 @@ int ftrace_update_ftrace_func(ftrace_func_t func) /* Also update the regs callback function */ if (!ret) { ip = (unsigned long)(&ftrace_regs_call); - old = *(struct ppc_inst *)&ftrace_regs_call; + old = ppc_inst_read((struct ppc_inst *)&ftrace_regs_call); new = ftrace_call_replace(ip, (unsigned long)func, 1); ret = ftrace_modify_code(ip, old, new); } diff --git a/arch/powerpc/kernel/uprobes.c b/arch/powerpc/kernel/uprobes.c index 31c870287f2b..6893d40a48c5 100644 --- a/arch/powerpc/kernel/uprobes.c +++ b/arch/powerpc/kernel/uprobes.c @@ -174,7 +174,7 @@ bool arch_uprobe_skip_sstep(struct arch_uprobe *auprobe, struct pt_regs *regs) * emulate_step() returns 1 if the insn was successfully emulated. * For all other cases, we need to single-step in hardware. */ - ret = emulate_step(regs, auprobe->insn); + ret = emulate_step(regs, ppc_inst_read(&auprobe->insn)); if (ret > 0) return true; diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c index 1dff9d9d6645..435fc8e9f45d 100644 --- a/arch/powerpc/lib/code-patching.c +++ b/arch/powerpc/lib/code-patching.c @@ -348,9 +348,9 @@ static unsigned long branch_bform_target(const struct ppc_inst *instr) unsigned long branch_target(const struct ppc_inst *instr) { - if (instr_is_branch_iform(*instr)) + if (instr_is_branch_iform(ppc_inst_read(instr))) return branch_iform_target(instr); - else if (instr_is_branch_bform(*instr)) + else if (instr_is_branch_bform(ppc_inst_read(instr))) return branch_bform_target(instr); return 0; @@ -358,7 +358,8 @@ unsigned long branch_target(const struct ppc_inst *instr) int instr_is_branch_to_addr(const struct ppc_inst *instr, unsigned long addr) { - if (instr_is_branch_iform(*instr) || instr_is_branch_bform(*instr)) + if (instr_is_branch_iform(ppc_inst_read(instr)) || + instr_is_branch_bform(ppc_inst_read(instr))) return branch_target(instr) == addr; return 0; @@ -368,13 +369,14 @@ int translate_branch(struct ppc_inst *instr, const struct ppc_inst *dest, const struct ppc_inst *src) { unsigned long target; - target = branch_target(src); - if (instr_is_branch_iform(*src)) - return create_branch(instr, dest, target, ppc_inst_val(*src)); - else if (instr_is_branch_bform(*src)) - return create_cond_branch(instr, dest, target, ppc_inst_val(*src)); + if (instr_is_branch_iform(ppc_inst_read(src))) + return create_branch(instr, dest, target, + ppc_inst_val(ppc_inst_read(src))); + else if (instr_is_branch_bform(ppc_inst_read(src))) + return create_cond_branch(instr, dest, target, + ppc_inst_val(ppc_inst_read(src))); return 1; } @@ -598,7 +600,7 @@ static void __init test_translate_branch(void) patch_instruction(q, instr); check(instr_is_branch_to_addr(p, addr)); check(instr_is_branch_to_addr(q, addr)); - check(ppc_inst_equal(*q, ppc_inst(0x4a000000))); + check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x4a000000))); /* Maximum positive case, move x to x - 32 MB + 4 */ p = buf + 0x2000000; @@ -609,7 +611,7 @@ static void __init test_translate_branch(void) patch_instruction(q, instr); check(instr_is_branch_to_addr(p, addr)); check(instr_is_branch_to_addr(q, addr)); - check(ppc_inst_equal(*q, ppc_inst(0x49fffffc))); + check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x49fffffc))); /* Jump to x + 16 MB moved to x + 20 MB */ p = buf; @@ -655,7 +657,7 @@ static void __init test_translate_branch(void) patch_instruction(q, instr); check(instr_is_branch_to_addr(p, addr)); check(instr_is_branch_to_addr(q, addr)); - check(ppc_inst_equal(*q, ppc_inst(0x43ff8000))); + check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x43ff8000))); /* Maximum positive case, move x to x - 32 KB + 4 */ p = buf + 0x8000; @@ -667,7 +669,7 @@ static void __init test_translate_branch(void) patch_instruction(q, instr); check(instr_is_branch_to_addr(p, addr)); check(instr_is_branch_to_addr(q, addr)); - check(ppc_inst_equal(*q, ppc_inst(0x43ff7ffc))); + check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x43ff7ffc))); /* Jump to x + 12 KB moved to x + 20 KB */ p = buf; diff --git a/arch/powerpc/lib/feature-fixups.c b/arch/powerpc/lib/feature-fixups.c index fb6e8e8abf4e..c0d3ed4efb7e 100644 --- a/arch/powerpc/lib/feature-fixups.c +++ b/arch/powerpc/lib/feature-fixups.c @@ -48,7 +48,7 @@ static int patch_alt_instruction(struct ppc_inst *src, struct ppc_inst *dest, int err; struct ppc_inst instr; - instr = *src; + instr = ppc_inst_read(src); if (instr_is_relative_branch(*src)) { struct ppc_inst *target = (struct ppc_inst *)branch_target(src); @@ -403,7 +403,7 @@ static void do_final_fixups(void) length = (__end_interrupts - _stext) / sizeof(struct ppc_inst); while (length--) { - raw_patch_instruction(dest, *src); + raw_patch_instruction(dest, ppc_inst_read(src)); src++; dest++; } diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c index e0132d6d24d0..68e0b05d9226 100644 --- a/arch/powerpc/xmon/xmon.c +++ b/arch/powerpc/xmon/xmon.c @@ -702,13 +702,13 @@ static int xmon_core(struct pt_regs *regs, int fromipi) if ((regs->msr & (MSR_IR|MSR_PR|MSR_64BIT)) == (MSR_IR|MSR_64BIT)) { bp = at_breakpoint(regs->nip); if (bp != NULL) { - int stepped = emulate_step(regs, bp->instr[0]); + int stepped = emulate_step(regs, ppc_inst_read(bp->instr)); if (stepped == 0) { regs->nip = (unsigned long) &bp->instr[0]; atomic_inc(&bp->ref_count); } else if (stepped < 0) { printf("Couldn't single-step %s instruction\n", - (IS_RFID(bp->instr[0])? "rfid": "mtmsrd")); + IS_RFID(ppc_inst_read(bp->instr))? "rfid": "mtmsrd"); } } } @@ -949,7 +949,7 @@ static void remove_bpts(void) if (mread(bp->address, &instr, 4) == 4 && ppc_inst_equal(instr, ppc_inst(bpinstr)) && patch_instruction( - (struct ppc_inst *)bp->address, bp->instr[0]) != 0) + (struct ppc_inst *)bp->address, ppc_inst_read(bp->instr)) != 0) printf("Couldn't remove breakpoint at %lx\n", bp->address); } -- 2.17.1