Re: [PATCH] powerpc/32s: Fix module loading failure when VMALLOC_END is over 0xf0000000

2020-08-27 Thread Michael Ellerman 
On Fri, 21 Aug 2020 07:15:25 + (UTC), Christophe Leroy wrote:
> In is_module_segment(), when VMALLOC_END is over 0xf000,
> 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 0x and will be suitable for the comparison.

Applied to powerpc/fixes.

[1/1] powerpc/32s: Fix module loading failure when VMALLOC_END is over 
0xf000
  https://git.kernel.org/powerpc/c/541cebb51f3422d4f2c6cb95c1e5cc3dcc9e5021

cheers

Re: [PATCH] powerpc/32s: Fix module loading failure when VMALLOC_END is over 0xf0000000

2020-08-21 Thread Andreas Schwab 
On Aug 21 2020, Christophe Leroy wrote:

> In is_module_segment(), when VMALLOC_END is over 0xf000,
> 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 0x and will be suitable for the comparison.
>
> Reported-by: Andreas Schwab 
> Signed-off-by: Christophe Leroy 
> Fixes: c49643319715 ("powerpc/32s: Only leave NX unset on segments used for 
> modules")

Thanks, that fixes the crash.

Tested-by: Andreas Schwab 

Andreas.

-- 
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[PATCH] powerpc/32s: Fix module loading failure when VMALLOC_END is over 0xf0000000

2020-08-21 Thread Christophe Leroy 
In is_module_segment(), when VMALLOC_END is over 0xf000,
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 0x and will be suitable for the comparison.

Reported-by: Andreas Schwab 
Signed-off-by: Christophe Leroy 
Fixes: c49643319715 ("powerpc/32s: Only leave NX unset on segments used for 
modules")
---
 arch/powerpc/mm/book3s32/mmu.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/mm/book3s32/mmu.c b/arch/powerpc/mm/book3s32/mmu.c
index 82ae9e06a773..d426eaf76bb0 100644
--- 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;
-- 
2.25.0