Patch "s390: make setup_randomness work" has been added to the 4.9-stable tree

Patch "s390: make setup_randomness work" has been added to the 4.9-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    s390: make setup_randomness work

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     s390-make-setup_randomness-work.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From da8fd820f389a0e29080b14c61bf5cf1d8ef5ca1 Mon Sep 17 00:00:00 2001
From: Heiko Carstens <heiko.carstens@de.ibm.com>
Date: Sat, 4 Feb 2017 11:40:36 +0100
Subject: s390: make setup_randomness work

From: Heiko Carstens <heiko.carstens@de.ibm.com>

commit da8fd820f389a0e29080b14c61bf5cf1d8ef5ca1 upstream.

Commit bcfcbb6bae64 ("s390: add system information as device
randomness") intended to add some virtual machine specific information
to the randomness pool.

Unfortunately it uses the page allocator before it is ready to use. In
result the page allocator always returns NULL and the setup_randomness
function never adds anything to the randomness pool.

To fix this use memblock_alloc and memblock_free instead.

Fixes: bcfcbb6bae64 ("s390: add system information as device randomness")
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/s390/kernel/setup.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -819,10 +819,10 @@ static void __init setup_randomness(void
 {
 	struct sysinfo_3_2_2 *vmms;
 
-	vmms = (struct sysinfo_3_2_2 *) alloc_page(GFP_KERNEL);
-	if (vmms && stsi(vmms, 3, 2, 2) == 0 && vmms->count)
+	vmms = (struct sysinfo_3_2_2 *) memblock_alloc(PAGE_SIZE, PAGE_SIZE);
+	if (stsi(vmms, 3, 2, 2) == 0 && vmms->count)
 		add_device_randomness(&vmms, vmms->count);
-	free_page((unsigned long) vmms);
+	memblock_free((unsigned long) vmms, PAGE_SIZE);
 }
 
 /*


Patches currently in stable-queue which might be from heiko.carstens@de.ibm.com are

queue-4.9/s390-use-correct-input-data-address-for-setup_randomness.patch
queue-4.9/s390-make-setup_randomness-work.patch