Messages in this thread | | | Subject | Re: remove the last set_fs() in common code, and remove it for x86 and powerpc v3 | From | Christophe Leroy <> | Date | Sat, 5 Sep 2020 09:16:06 +0200 |
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Le 04/09/2020 à 23:01, David Laight a écrit : > From: Alexey Dobriyan >> Sent: 04 September 2020 18:58 >> >> On Fri, Sep 04, 2020 at 08:00:24AM +0200, Ingo Molnar wrote: >>> * Christoph Hellwig <hch@lst.de> wrote: >>>> this series removes the last set_fs() used to force a kernel address >>>> space for the uaccess code in the kernel read/write/splice code, and then >>>> stops implementing the address space overrides entirely for x86 and >>>> powerpc. >>> >>> Cool! For the x86 bits: >>> >>> Acked-by: Ingo Molnar <mingo@kernel.org> >> >> set_fs() is older than some kernel hackers! >> >> $ cd linux-0.11/ >> $ find . -type f -name '*.h' | xargs grep -e set_fs -w -n -A3 >> ./include/asm/segment.h:61:extern inline void set_fs(unsigned long val) >> ./include/asm/segment.h-62-{ >> ./include/asm/segment.h-63- __asm__("mov %0,%%fs"::"a" ((unsigned short) val)); >> ./include/asm/segment.h-64-} > > What is this strange %fs register you are talking about. > Figure 2-4 only has CS, DS, SS and ES. >
Intel added registers FS and GS in the i386
Christophe
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