Messages in this thread | | | Date | Wed, 2 Jan 2008 03:31:26 +0200 | From | Adrian Bunk <> | Subject | Re: asm-x86/byteorder.h: clean up for userspace |
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On Tue, Jan 01, 2008 at 01:19:42PM -0800, H. Peter Anvin wrote: > Christoph Hellwig wrote: >> On Mon, Dec 31, 2007 at 01:12:45PM -0500, Mike Frysinger wrote: >>> Since asm-x86/byteorder.h is exported to userspace, use __asm__ rather than >>> asm in its code. >> >> The correct fix is to not export it to userspace. > > Unfortunately, it's historically been provided, for over 15 years. It's > also trivial to export, without funnies, and it's *useful* to userspace, as > it provides an interface sorely lacking from the stock libc interfaces. >...
Userspace either has to #define CONFIG_X86_BSWAP or it'll get the slow versions of these functions...
Leaking CONFIG_ variables to userspace is not really funny - I remember e.g. what tricks MySQL does (did?) for (ab)using asm-i386/atomic.h in userspace.
> -hpa
cu Adrian
--
"Is there not promise of rain?" Ling Tan asked suddenly out of the darkness. There had been need of rain for many days. "Only a promise," Lao Er said. Pearl S. Buck - Dragon Seed
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