latent_entropy: Fix wrong gcc code generation with 64 bit variables
The stack frame size could grow too large when the plugin used long long
on 32-bit architectures when the given function had too many basic blocks.
The gcc warning was:
drivers/pci/hotplug/ibmphp_ebda.c: In function 'ibmphp_access_ebda':
drivers/pci/hotplug/ibmphp_ebda.c:409:1: warning: the frame size of 1108 bytes is larger than 1024 bytes [-Wframe-larger-than=]
This switches latent_entropy from u64 to unsigned long.
Thanks to PaX Team and Emese Revfy for the patch.
Signed-off-by: Kees Cook <keescook@chromium.org>
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 2b3bf67..1b10c14 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -92,7 +92,7 @@ int _node_numa_mem_[MAX_NUMNODES];
#endif
#ifdef CONFIG_GCC_PLUGIN_LATENT_ENTROPY
-volatile u64 latent_entropy __latent_entropy;
+volatile unsigned long latent_entropy __latent_entropy;
EXPORT_SYMBOL(latent_entropy);
#endif