Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > linux.kernel > #1168590
| From | Borislav Petkov <bp@alien8.de> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | [PATCH] x86/head_32: Fix overflow warning with 32-bit binutils |
| Date | 2015-06-19 10:00 +0200 |
| Message-ID | <pCZns-17v-9@gated-at.bofh.it> (permalink) |
| Organization | linux.* mail to news gateway |
From: Borislav Petkov <bp@suse.de> When building the kernel with 32-bit binutils built with support only for the i386 target, we get the following warning: arch/x86/kernel/head_32.S:66: Warning: shift count out of range (32 is not between 0 and 31) The problem is that in that case, binutils' internal type representation is 32-bit wide and the shift range overflows. In order to fix this, manipulate the shift expression which creates the 4GiB constant to not overflow the shift count. Reported-and-tested-by: Enrico Mioso <mrkiko.rs@gmail.com> Suggested-by: Michael Matz <matz@suse.de> Signed-off-by: Borislav Petkov <bp@suse.de> --- arch/x86/kernel/head_32.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S index 53eeb226657c..c601d1de5ae5 100644 --- a/arch/x86/kernel/head_32.S +++ b/arch/x86/kernel/head_32.S @@ -63,8 +63,8 @@ #endif /* Number of possible pages in the lowmem region */ -LOWMEM_PAGES = (((1<<32) - __PAGE_OFFSET) >> PAGE_SHIFT) - +LOWMEM_PAGES = (((2<<31) - __PAGE_OFFSET) >> PAGE_SHIFT) + /* Enough space to fit pagetables for the low memory linear map */ MAPPING_BEYOND_END = PAGE_TABLE_SIZE(LOWMEM_PAGES) << PAGE_SHIFT -- 2.3.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Back to linux.kernel | Previous | Next — Next in thread | Find similar | Unroll thread
[PATCH] x86/head_32: Fix overflow warning with 32-bit binutils Borislav Petkov <bp@alien8.de> - 2015-06-19 10:00 +0200
Re: [PATCH] x86/head_32: Fix overflow warning with 32-bit binutils Ingo Molnar <mingo@kernel.org> - 2015-06-19 10:20 +0200
Re: [PATCH] x86/head_32: Fix overflow warning with 32-bit binutils Borislav Petkov <bp@alien8.de> - 2015-06-19 11:00 +0200
csiph-web