linux-kernel - [PATCH]x86 efi: do not export efi runtime map in case old map

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 for Android: free password hash cracker in your pocket

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

Date:	Fri, 30 May 2014 11:20:10 +0800
From:	Dave Young <dyoung@...hat.com>
To:	matt.fleming@...el.com, bp@...en8.de, linux-kernel@...r.kernel.org,
	linux-efi@...r.kernel.org, vgoyal@...hat.com
Subject: [PATCH]x86 efi: do not export efi runtime map in case old map


For ioremapped efi memory aka old_map the virt addresses are not persistant
across kexec reboot. kexec-tools will read the runtime maps from sysfs then
pass them to 2nd kernel and assuming kexec efi boot is ok. This will cause
kexec boot failure.

To address this issue do not export runtime maps in case efi old_map so
userspace can use no efi boot instead.

Signed-off-by: Dave Young <dyoung@...hat.com>
---
 arch/x86/platform/efi/efi.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 3781dd3..4d36932 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -919,6 +919,9 @@ static void __init save_runtime_map(void)
 	void *tmp, *p, *q = NULL;
 	int count = 0;
 
+	if (efi_enabled(EFI_OLD_MEMMAP))
+		return;
+
 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
 		md = p;
 
-- 
1.8.3.1

--
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/