powerpc/32s: Fix module loading failure when VMALLOC_END is over 0xf0000000

In is_module_segment(), when VMALLOC_END is over 0xf0000000,
ALIGN(VMALLOC_END, SZ_256M) has value 0.

In that case, addr >= ALIGN(VMALLOC_END, SZ_256M) is always
true then is_module_segment() always returns false.

Use (ALIGN(VMALLOC_END, SZ_256M) - 1) which will have
value 0xffffffff and will be suitable for the comparison.

Fixes: c49643319715 ("powerpc/32s: Only leave NX unset on segments used for modules")
Reported-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Tested-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/09fc73fe9c7423c6b4cf93f93df9bb0ed8eefab5.1597994047.git.christophe.leroy@csgroup.eu

diff --git a/arch/powerpc/mm/book3s32/mmu.c b/arch/powerpc/mm/book3s32/mmu.c
index 82ae9e0..d426eaf 100644 (file)
--- a/arch/powerpc/mm/book3s32/mmu.c
+++ b/arch/powerpc/mm/book3s32/mmu.c
@@ -194,12 +194,12 @@ static bool is_module_segment(unsigned long addr)
 #ifdef MODULES_VADDR
        if (addr < ALIGN_DOWN(MODULES_VADDR, SZ_256M))
                return false;
-       if (addr >= ALIGN(MODULES_END, SZ_256M))
+       if (addr > ALIGN(MODULES_END, SZ_256M) - 1)
                return false;
 #else
        if (addr < ALIGN_DOWN(VMALLOC_START, SZ_256M))
                return false;
-       if (addr >= ALIGN(VMALLOC_END, SZ_256M))
+       if (addr > ALIGN(VMALLOC_END, SZ_256M) - 1)
                return false;
 #endif
        return true;