From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mx1.redhat.com ([209.132.183.28]) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1chDHR-0005qg-6L for kexec@lists.infradead.org; Fri, 24 Feb 2017 10:39:19 +0000 From: Baoquan He Subject: [PATCH] Only search page_offset_base when KASLR mm code is compiled in Date: Fri, 24 Feb 2017 18:38:52 +0800 Message-Id: <1487932732-24539-1-git-send-email-bhe@redhat.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: horms@verge.net.au Cc: kexec@lists.infradead.org, Baoquan He , piliu@redhat.com Otherwise it will print false positve message as below. So add a check when do the search. "Cannot get kernel page_offset_base symbol address" Signed-off-by: Baoquan He --- kexec/arch/i386/crashdump-x86.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/kexec/arch/i386/crashdump-x86.c b/kexec/arch/i386/crashdump-x86.c index 88aeee3..b2c1be5 100644 --- a/kexec/arch/i386/crashdump-x86.c +++ b/kexec/arch/i386/crashdump-x86.c @@ -150,8 +150,6 @@ static int get_kernel_vaddr_and_size(struct kexec_info *UNUSED(info), off_t size; uint32_t elf_flags = 0; uint64_t stext_sym; - const unsigned long long pud_mask = ~((1 << 30) - 1); - unsigned long long vaddr, lowest_vaddr = 0; if (elf_info->machine != EM_X86_64) return 0; @@ -181,8 +179,11 @@ static int get_kernel_vaddr_and_size(struct kexec_info *UNUSED(info), end_phdr = &ehdr.e_phdr[ehdr.e_phnum]; +#ifdef CONFIG_RANDOMIZE_MEMORY /* Search for the real PAGE_OFFSET when KASLR memory randomization * is enabled */ + const unsigned long long pud_mask = ~((1 << 30) - 1); + unsigned long long vaddr, lowest_vaddr = 0; if (get_kernel_sym("page_offset_base") != 0) { for(phdr = ehdr.e_phdr; phdr != end_phdr; phdr++) { if (phdr->p_type == PT_LOAD) { @@ -194,6 +195,7 @@ static int get_kernel_vaddr_and_size(struct kexec_info *UNUSED(info), if (lowest_vaddr != 0) elf_info->page_offset = lowest_vaddr; } +#endif /* Traverse through the Elf headers and find the region where * _stext symbol is located in. That's where kernel is mapped */ -- 2.5.5 _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec