s390: make setup_randomness work

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>

diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index 1f581eb61bc20f928fffb6e065cfcf6100a9a2a8..1cf4aae767804afabbbe6f42db706428e8588ff8 100644 (file)
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -805,10 +805,10 @@ 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);
 }
 
 /*