On Fri, Oct 30, 2020 at 4:49 PM Arnd Bergmann <arnd@xxxxxxxxxx> wrote: > From: Arnd Bergmann <arnd@xxxxxxxx> > > ARM uses set_fs() and __get_user() to allow the stack dumping code to > access possibly invalid pointers carefully. These can be changed to the > simpler get_kernel_nofault(), and allow the eventual removal of set_fs(). > > dump_instr() will print either kernel or user space pointers, > depending on how it was called. For dump_mem(), I assume we are only > interested in kernel pointers, and the only time that this is called > with user_mode(regs)==true is when the regs themselves are unreliable > as a result of the condition that caused the trap. > > Reviewed-by: Christoph Hellwig <hch@xxxxxx> > Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> Not to mention the drastically improved readability of the code, as ARM developers no more needs to cross-reference the x86 FS segment register to figure out what this might be doing. Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx> Yours, Linus Walleij
