Le 04/09/2020 à 23:01, David Laight a écrit :

From: Alexey Dobriyan

quoted

Sent: 04 September 2020 18:58

On Fri, Sep 04, 2020 at 08:00:24AM +0200, Ingo Molnar wrote:

quoted

* Christoph Hellwig [off-list ref] wrote:

quoted

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 [off-list ref]

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