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[209.132.180.67]) by mx.google.com with ESMTP id w5-v6si10684393plz.551.2018.03.06.02.24.27; Tue, 06 Mar 2018 02:24:27 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@linaro.org header.s=google header.b=gaUn6etB; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linaro.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753475AbeCFKXa (ORCPT + 28 others); Tue, 6 Mar 2018 05:23:30 -0500 Received: from mail-io0-f194.google.com ([209.85.223.194]:41864 "EHLO mail-io0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753442AbeCFKX0 (ORCPT ); Tue, 6 Mar 2018 05:23:26 -0500 Received: by mail-io0-f194.google.com with SMTP id q24so21464343ioh.8 for ; Tue, 06 Mar 2018 02:23:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=+vdHx8igNuwtKYBwEka16s0oES3aT+sWWLO70kkZrSg=; b=gaUn6etBk+tP09kV0mX+o/d6dwlbT18KJBg3aRajKzQriZ38t10S2XcqSJcuDcDj/i mHp2dOuOCIPwltDWJ0lQ/DyeUvFClKQcFltQ1L5pSJi29SoNVSZ8bYC+ZjoeoFTeuY95 iY6KkXb8YaprU0KWVxX9sk6kF4npOa967ycvY= 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=+vdHx8igNuwtKYBwEka16s0oES3aT+sWWLO70kkZrSg=; b=WxjZdEnYRBzjH4fy+4lq1vUevhZ4im/tsMl1k3TbQfUKsLKjQjgCUCIYIML7CjXCJH KoO36e8C2WvSB3nGwwbu0b1FS4TSPag5kbm2p7srkQmnuXfHm8NmmXwxWx7ldgpZCnR1 N450rGwGDrHX9scYH5Gl9PzII41LMBqN1LrETOVXrgg0ibtvgUPR3yGwwq02GaW2fwSP 8Vw7AYRGX0rh6l0oCmygSJoEX+U00gLrSvh+Kn1BfRvb99QuoG4+eiY8MhLjtq1wl2go Z7tiaIG1ZxYgpYbfwRVM4af9qXvt+Z3GkSjXazJGpCQpTuw71pPh7Mqmyxc/UIfS6/V5 ecNg== X-Gm-Message-State: APf1xPBDPasH8xzef86EyLpcmuaotsxG8320uiRW0/1OytY0wzSSQFyB 52BjgpdbhxP5kHzJBl9DYztQwQ== X-Received: by 10.107.143.23 with SMTP id r23mr20762572iod.191.1520331805415; Tue, 06 Mar 2018 02:23:25 -0800 (PST) Received: from linaro.org ([121.95.100.191]) by smtp.googlemail.com with ESMTPSA id n22sm9691145iob.62.2018.03.06.02.23.24 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 06 Mar 2018 02:23:24 -0800 (PST) From: AKASHI Takahiro To: dyoung@redhat.com, vgoyal@redhat.com, bhe@redhat.com, mpe@ellerman.id.au, bauerman@linux.vnet.ibm.com, prudo@linux.vnet.ibm.com Cc: kexec@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, AKASHI Takahiro Subject: [PATCH v2 3/7] x86: kexec_file: purge system-ram walking from prepare_elf64_headers() Date: Tue, 6 Mar 2018 19:22:59 +0900 Message-Id: <20180306102303.9063-4-takahiro.akashi@linaro.org> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180306102303.9063-1-takahiro.akashi@linaro.org> References: <20180306102303.9063-1-takahiro.akashi@linaro.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org While prepare_elf64_headers() in x86 looks pretty generic for other architectures' use, it contains some code which tries to list crash memory regions by walking through system resources, which is not always architecture agnostic. To make this function more generic, the related code should be purged. In this patch, prepare_elf64_headers() simply scans crash_mem buffer passed and add all the listed regions to elf header as a PT_LOAD segment. So walk_system_ram_res(prepare_elf64_headers_callback) have been moved forward before prepare_elf64_headers() where the callback, prepare_elf64_headers_callback(), is now responsible for filling up crash_mem buffer. Meanwhile exclude_elf_header_ranges() used to be called every time in this callback it is rather redundant and now called only once in prepare_elf_headers() as well. Signed-off-by: AKASHI Takahiro Cc: Dave Young Cc: Vivek Goyal Cc: Baoquan He --- arch/x86/kernel/crash.c | 121 +++++++++++++++++++++++------------------------- 1 file changed, 58 insertions(+), 63 deletions(-) -- 2.16.2 diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c index 10e74d4778a1..2123fa0efc17 100644 --- a/arch/x86/kernel/crash.c +++ b/arch/x86/kernel/crash.c @@ -316,18 +316,11 @@ static int exclude_mem_range(struct crash_mem *mem, * Look for any unwanted ranges between mstart, mend and remove them. This * might lead to split and split ranges are put in ced->mem.ranges[] array */ -static int elf_header_exclude_ranges(struct crash_elf_data *ced, - unsigned long long mstart, unsigned long long mend) +static int elf_header_exclude_ranges(struct crash_elf_data *ced) { struct crash_mem *cmem = &ced->mem; int ret = 0; - memset(cmem->ranges, 0, sizeof(cmem->ranges)); - - cmem->ranges[0].start = mstart; - cmem->ranges[0].end = mend; - cmem->nr_ranges = 1; - /* Exclude crashkernel region */ ret = exclude_mem_range(cmem, crashk_res.start, crashk_res.end); if (ret) @@ -345,53 +338,13 @@ static int elf_header_exclude_ranges(struct crash_elf_data *ced, static int prepare_elf64_ram_headers_callback(struct resource *res, void *arg) { struct crash_elf_data *ced = arg; - Elf64_Ehdr *ehdr; - Elf64_Phdr *phdr; - unsigned long mstart, mend; - struct kimage *image = ced->image; - struct crash_mem *cmem; - int ret, i; - - ehdr = ced->ehdr; - - /* Exclude unwanted mem ranges */ - ret = elf_header_exclude_ranges(ced, res->start, res->end); - if (ret) - return ret; - - /* Go through all the ranges in ced->mem.ranges[] and prepare phdr */ - cmem = &ced->mem; - - for (i = 0; i < cmem->nr_ranges; i++) { - mstart = cmem->ranges[i].start; - mend = cmem->ranges[i].end; - - phdr = ced->bufp; - ced->bufp += sizeof(Elf64_Phdr); + struct crash_mem *cmem = &ced->mem; - phdr->p_type = PT_LOAD; - phdr->p_flags = PF_R|PF_W|PF_X; - phdr->p_offset = mstart; + cmem->ranges[cmem->nr_ranges].start = res->start; + cmem->ranges[cmem->nr_ranges].end = res->end; + cmem->nr_ranges++; - /* - * If a range matches backup region, adjust offset to backup - * segment. - */ - if (mstart == image->arch.backup_src_start && - (mend - mstart + 1) == image->arch.backup_src_sz) - phdr->p_offset = image->arch.backup_load_addr; - - phdr->p_paddr = mstart; - phdr->p_vaddr = (unsigned long long) __va(mstart); - phdr->p_filesz = phdr->p_memsz = mend - mstart + 1; - phdr->p_align = 0; - ehdr->e_phnum++; - pr_debug("Crash PT_LOAD elf header. phdr=%p vaddr=0x%llx, paddr=0x%llx, sz=0x%llx e_phnum=%d p_offset=0x%llx\n", - phdr, phdr->p_vaddr, phdr->p_paddr, phdr->p_filesz, - ehdr->e_phnum, phdr->p_offset); - } - - return ret; + return 0; } static int prepare_elf64_headers(struct crash_elf_data *ced, @@ -401,9 +354,10 @@ static int prepare_elf64_headers(struct crash_elf_data *ced, Elf64_Phdr *phdr; unsigned long nr_cpus = num_possible_cpus(), nr_phdr, elf_sz; unsigned char *buf, *bufp; - unsigned int cpu; + unsigned int cpu, i; unsigned long long notes_addr; - int ret; + struct crash_mem *cmem = &ced->mem; + unsigned long mstart, mend; /* extra phdr for vmcoreinfo elf note */ nr_phdr = nr_cpus + 1; @@ -472,13 +426,25 @@ static int prepare_elf64_headers(struct crash_elf_data *ced, (ehdr->e_phnum)++; #endif - /* Prepare PT_LOAD headers for system ram chunks. */ - ced->ehdr = ehdr; - ced->bufp = bufp; - ret = walk_system_ram_res(0, -1, ced, - prepare_elf64_ram_headers_callback); - if (ret < 0) - return ret; + /* Go through all the ranges in cmem->ranges[] and prepare phdr */ + for (i = 0; i < cmem->nr_ranges; i++) { + mstart = cmem->ranges[i].start; + mend = cmem->ranges[i].end; + + phdr->p_type = PT_LOAD; + phdr->p_flags = PF_R|PF_W|PF_X; + phdr->p_offset = mstart; + + phdr->p_paddr = mstart; + phdr->p_vaddr = (unsigned long long) __va(mstart); + phdr->p_filesz = phdr->p_memsz = mend - mstart + 1; + phdr->p_align = 0; + ehdr->e_phnum++; + phdr++; + pr_debug("Crash PT_LOAD elf header. phdr=%p vaddr=0x%llx, paddr=0x%llx, sz=0x%llx e_phnum=%d p_offset=0x%llx\n", + phdr, phdr->p_vaddr, phdr->p_paddr, phdr->p_filesz, + ehdr->e_phnum, phdr->p_offset); + } *addr = buf; *sz = elf_sz; @@ -490,7 +456,9 @@ static int prepare_elf_headers(struct kimage *image, void **addr, unsigned long *sz) { struct crash_elf_data *ced; - int ret; + Elf64_Ehdr *ehdr; + Elf64_Phdr *phdr; + int ret, i; ced = kzalloc(sizeof(*ced), GFP_KERNEL); if (!ced) @@ -498,8 +466,35 @@ static int prepare_elf_headers(struct kimage *image, void **addr, fill_up_crash_elf_data(ced, image); + ret = walk_system_ram_res(0, -1, ced, + prepare_elf64_ram_headers_callback); + if (ret) + goto out; + + /* Exclude unwanted mem ranges */ + ret = elf_header_exclude_ranges(ced); + if (ret) + goto out; + /* By default prepare 64bit headers */ ret = prepare_elf64_headers(ced, addr, sz); + if (ret) + goto out; + + /* + * If a range matches backup region, adjust offset to backup + * segment. + */ + ehdr = (Elf64_Ehdr *)*addr; + phdr = (Elf64_Phdr *)(ehdr + 1); + for (i = 0; i < ehdr->e_phnum; phdr++, i++) + if (phdr->p_type == PT_LOAD && + phdr->p_paddr == image->arch.backup_src_start && + phdr->p_memsz == image->arch.backup_src_sz) { + phdr->p_offset = image->arch.backup_load_addr; + break; + } +out: kfree(ced); return ret; }