From 736706bee3298208343a76096370e4f6a5c55915 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Mon, 4 Mar 2019 10:39:05 -0800 Subject: get rid of legacy 'get_ds()' function Every in-kernel use of this function defined it to KERNEL_DS (either as an actual define, or as an inline function). It's an entirely historical artifact, and long long long ago used to actually read the segment selector valueof '%ds' on x86. Which in the kernel is always KERNEL_DS. Inspired by a patch from Jann Horn that just did this for a very small subset of users (the ones in fs/), along with Al who suggested a script. I then just took it to the logical extreme and removed all the remaining gunk. Roughly scripted with git grep -l '(get_ds())' -- :^tools/ | xargs sed -i 's/(get_ds())/(KERNEL_DS)/' git grep -lw 'get_ds' -- :^tools/ | xargs sed -i '/^#define get_ds()/d' plus manual fixups to remove a few unusual usage patterns, the couple of inline function cases and to fix up a comment that had become stale. The 'get_ds()' function remains in an x86 kvm selftest, since in user space it actually does something relevant. Inspired-by: Jann Horn Inspired-by: Al Viro Signed-off-by: Linus Torvalds --- arch/nds32/include/asm/uaccess.h | 1 - arch/nds32/kernel/process.c | 2 +- 2 files changed, 1 insertion(+), 2 deletions(-) (limited to 'arch/nds32') diff --git a/arch/nds32/include/asm/uaccess.h b/arch/nds32/include/asm/uaccess.h index 53dcb49b0b12..116598b47c4d 100644 --- a/arch/nds32/include/asm/uaccess.h +++ b/arch/nds32/include/asm/uaccess.h @@ -37,7 +37,6 @@ extern int fixup_exception(struct pt_regs *regs); #define KERNEL_DS ((mm_segment_t) { ~0UL }) #define USER_DS ((mm_segment_t) {TASK_SIZE - 1}) -#define get_ds() (KERNEL_DS) #define get_fs() (current_thread_info()->addr_limit) #define user_addr_max get_fs diff --git a/arch/nds32/kernel/process.c b/arch/nds32/kernel/process.c index ab7ab46234b1..9712fd474f2c 100644 --- a/arch/nds32/kernel/process.c +++ b/arch/nds32/kernel/process.c @@ -121,7 +121,7 @@ void show_regs(struct pt_regs *regs) regs->uregs[3], regs->uregs[2], regs->uregs[1], regs->uregs[0]); pr_info(" IRQs o%s Segment %s\n", interrupts_enabled(regs) ? "n" : "ff", - segment_eq(get_fs(), get_ds())? "kernel" : "user"); + segment_eq(get_fs(), KERNEL_DS)? "kernel" : "user"); } EXPORT_SYMBOL(show_regs); -- cgit v1.2.3-59-g8ed1b