ARM: initrd: disable initrd if passed address overlaps reserved region

commit b0a2679d27408d97ce31e5f800b44227d3388b84 upstream.

Disable the initrd if the passed address already overlaps the reserved
region.  This avoids oopses on Netwinders when NeTTrom tells the kernel
that an initrd is located at mem+4MB, but this overlaps the BSS,
resulting in the kernels in-use BSS being freed.

This should be applied to v2.6.37-stable.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c
index 7185b00650fe419d0fa0f43b3e79e2e0d90cf6e6..4e2f620de09b80699dae7726d2de003a9db5b9fd 100644 (file)
--- a/arch/arm/mm/init.c
+++ b/arch/arm/mm/init.c
@@ -282,6 +282,12 @@ void __init arm_memblock_init(struct meminfo *mi, struct machine_desc *mdesc)
        memblock_reserve(__pa(_stext), _end - _stext);
 #endif
 #ifdef CONFIG_BLK_DEV_INITRD
+       if (phys_initrd_size &&
+           memblock_is_region_reserved(phys_initrd_start, phys_initrd_size)) {
+               pr_err("INITRD: 0x%08lx+0x%08lx overlaps in-use memory region - disabling initrd\n",
+                      phys_initrd_start, phys_initrd_size);
+               phys_initrd_start = phys_initrd_size = 0;
+       }
        if (phys_initrd_size) {
                memblock_reserve(phys_initrd_start, phys_initrd_size);