From: Peter Stuge <peter@stuge.se>
Date: Thu, 22 Jan 2009 22:53:59 +0000 (+0000)
Subject: flashrom: Provide some hints for the user in case /dev/mem mmap fails.
X-Git-Url: http://wien.tomnetworks.com/gitweb/?a=commitdiff_plain;h=8a681b1d840e701e41892f8375a15baf56107ab5;p=coreboot.git

flashrom: Provide some hints for the user in case /dev/mem mmap fails.

resolves #121

Signed-off-by: Peter Stuge <peter@stuge.se>
Acked-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>


git-svn-id: svn://svn.coreboot.org/coreboot/trunk@3889 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1
---

diff --git a/util/flashrom/flashrom.c b/util/flashrom/flashrom.c
index f613f8a07..7e52fbc8d 100644
--- a/util/flashrom/flashrom.c
+++ b/util/flashrom/flashrom.c
@@ -139,6 +139,13 @@ struct flashchip *probe_flash(struct flashchip *first_flash, int force)
 			    fd_mem, (off_t) base);
 		if (bios == MAP_FAILED) {
 			perror("Can't mmap memory using " MEM_DEV);
+			if (EINVAL == errno) {
+				fprintf(stderr, "In Linux this error can be caused by the CONFIG_NONPROMISC_DEVMEM (<2.6.27),\n");
+				fprintf(stderr, "CONFIG_STRICT_DEVMEM (>=2.6.27) and CONFIG_X86_PAT kernel options.\n");
+				fprintf(stderr, "Please check if either is enabled in your kernel before reporting a failure.\n");
+				fprintf(stderr, "You can override CONFIG_X86_PAT at boot with the nopat kernel parameter but\n");
+				fprintf(stderr, "disabling the other option unfortunately requires a kernel recompile. Sorry!\n");
+			}
 			exit(1);
 		}
 		flash->virtual_memory = bios;