Hi,

-----Original Message-----
From: Rafael J. Wysocki [mailto:rjw@rjwysocki.net]
Sent: Thursday, September 29, 2016 8:25 PM
To: Stephen Rothwell
Cc: Thomas Gleixner; Ingo Molnar; H. Peter Anvin; Peter Zijlstra; linux-
next@vger.kernel.org; linux-kernel@vger.kernel.org; Denys Vlasenko; Chen, Yu
C
Subject: Re: linux-next: build failure after merge of the tip tree

On Thursday, September 29, 2016 01:20:07 PM Stephen Rothwell wrote:

quoted

Hi all,

After merging the tip tree, today's linux-next build (x86_64
allmodconfig) failed like this:

arch/x86/power/hibernate_64.c: In function 'hibernation_e820_save':
arch/x86/power/hibernate_64.c:236:15: error: passing argument 1 of

'get_e820_md5' from incompatible pointer type [-Werror=incompatible-
pointer-types]

quoted

  get_e820_md5(&e820_saved, buf);
               ^
arch/x86/power/hibernate_64.c:203:12: note: expected 'struct e820map *'

but argument is of type 'struct e820map **'

quoted

 static int get_e820_md5(struct e820map *map, void *buf)
            ^
arch/x86/power/hibernate_64.c: In function 'hibernation_e820_mismatch':
arch/x86/power/hibernate_64.c:249:21: error: passing argument 1 of

'get_e820_md5' from incompatible pointer type [-Werror=incompatible-
pointer-types]

quoted

  ret = get_e820_md5(&e820_saved, result);
                     ^
arch/x86/power/hibernate_64.c:203:12: note: expected 'struct e820map *'

but argument is of type 'struct e820map **'

quoted

 static int get_e820_md5(struct e820map *map, void *buf)
            ^

Caused by commit

  475339684ef1 ("x86/e820: Prepare e280 code for switch to dynamic
storage")

interacting with commit

  6f95ad2b6162 ("PM / hibernate: Verify e820 memory map by MD5
digest")

from the pm tree.

I have applied the following merge fix patch:

From: Stephen Rothwell <redacted>
Date: Thu, 29 Sep 2016 13:13:45 +1000
Subject: [PATCH] pm/hibernate: merge fix for type of e820_saved
changing

Signed-off-by: Stephen Rothwell <redacted>
---
 arch/x86/power/hibernate_64.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/power/hibernate_64.c

b/arch/x86/power/hibernate_64.c index 72f2c9531b03..904048f7a9c9
100644

--- a/arch/x86/power/hibernate_64.c
+++ b/arch/x86/power/hibernate_64.c

@@ -233,7 +233,7 @@ static int get_e820_md5(struct e820map *map, void

*buf)

 static void hibernation_e820_save(void *buf)  {
-	get_e820_md5(&e820_saved, buf);
+	get_e820_md5(e820_saved, buf);
 }

 static bool hibernation_e820_mismatch(void *buf) @@ -246,7 +246,7 @@
static bool hibernation_e820_mismatch(void *buf)
 	if (!memcmp(result, buf, MD5_DIGEST_SIZE))
 		return false;

-	ret = get_e820_md5(&e820_saved, result);
+	ret = get_e820_md5(e820_saved, result);
 	if (ret)
 		return true;

Looks good to me, thanks Stephen!

Rafael

Thanks for the fix!

I made a double check of the patch :
"x86/e820: Prepare e280 code for switch to dynamic storage"
It looks like this patch has reallocate the e820 & e820_save to their actual size:
+	size = offsetof(struct e820map, map) + sizeof(struct e820entry) * e820->nr_map;
+	n = kmalloc(size, GFP_KERNEL);

however the previous patch to verify the md5 hash during hibernation will
use the original e820_map structure by sizeof(struct e820map), which might 
read invalid value after the latest patch applied. I think I need to modify the 
hibernation e820 checking patch to only generate  md5 digest based on the actual 
e820_save size by sizeof(struct e820entry) * e820->nr_map.

I don't have a machine in hand now, will test later and give feedback later. Thanks again!
Yu