linux-kernel - [RFC PATCH v4 06/10] fadump: Add PT_NOTE program header for vmcoreinfo

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20111107095603.1997.39898.stgit@mars.in.ibm.com>
Date:	Mon, 07 Nov 2011 15:26:04 +0530
From:	Mahesh J Salgaonkar <mahesh@...ux.vnet.ibm.com>
To:	linuxppc-dev <linuxppc-dev@...abs.org>,
	Linux Kernel <linux-kernel@...r.kernel.org>,
	Benjamin Herrenschmidt <benh@...nel.crashing.org>
Cc:	Amerigo Wang <amwang@...hat.com>,
	Ananth Narayan <ananth@...ibm.com>,
	Milton Miller <miltonm@....com>,
	Haren Myneni <hbabu@...ibm.com>,
	Anton Blanchard <anton@...ba.org>,
	"Eric W. Biederman" <ebiederm@...ssion.com>
Subject: [RFC PATCH v4 06/10] fadump: Add PT_NOTE program header for vmcoreinfo

From: Mahesh Salgaonkar <mahesh@...ux.vnet.ibm.com>

Introduce a PT_NOTE program header that points to physical address of
vmcoreinfo_note buffer declared in kernel/kexec.c. The vmcoreinfo
note buffer is populated during crash_fadump() at the time of system
crash.

Signed-off-by: Mahesh Salgaonkar <mahesh@...ux.vnet.ibm.com>
---
 arch/powerpc/kernel/fadump.c |   29 +++++++++++++++++++++++++++++
 1 files changed, 29 insertions(+), 0 deletions(-)

diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c
index 70d6287..e68ee3a 100644
--- a/arch/powerpc/kernel/fadump.c
+++ b/arch/powerpc/kernel/fadump.c
@@ -816,6 +816,19 @@ static void setup_crash_memory_ranges(void)
 	}
 }
 
+/*
+ * If the given physical address falls within the boot memory region then
+ * return the relocated address that points to the dump region reserved
+ * for saving initial boot memory contents.
+ */
+static inline unsigned long relocate(unsigned long paddr)
+{
+	if (paddr > RMR_START && paddr < fw_dump.boot_memory_size)
+		return fdm.rmr_region.destination_address + paddr;
+	else
+		return paddr;
+}
+
 static int create_elfcore_headers(char *bufp)
 {
 	struct elfhdr *elf;
@@ -847,6 +860,22 @@ static int create_elfcore_headers(char *bufp)
 
 	(elf->e_phnum)++;
 
+	/* setup ELF PT_NOTE for vmcoreinfo */
+	phdr = (struct elf_phdr *)bufp;
+	bufp += sizeof(struct elf_phdr);
+	phdr->p_type	= PT_NOTE;
+	phdr->p_flags	= 0;
+	phdr->p_vaddr	= 0;
+	phdr->p_align	= 0;
+
+	phdr->p_paddr	= relocate(paddr_vmcoreinfo_note());
+	phdr->p_offset	= phdr->p_paddr;
+	phdr->p_memsz	= vmcoreinfo_max_size;
+	phdr->p_filesz	= vmcoreinfo_max_size;
+
+	/* Increment number of program headers. */
+	(elf->e_phnum)++;
+
 	/* setup PT_LOAD sections. */
 
 	for (i = 0; i < crash_mem_ranges; i++) {

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/