diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-03-04 10:39:05 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-03-04 10:50:14 -0800 |
| commit | 736706bee3298208343a76096370e4f6a5c55915 (patch) | |
| tree | 3e90fd9d540cb15ac671182d52f9a4ade8657c59 /arch/arm | |
| parent | 84c4e1f89fefe70554da0ab33be72c9be7994379 (diff) | |
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 <jannh@google.com>
Inspired-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/arm')
| -rw-r--r-- | arch/arm/include/asm/uaccess.h | 1 | ||||
| -rw-r--r-- | arch/arm/kernel/process.c | 2 | ||||
| -rw-r--r-- | arch/arm/xen/hypercall.S | 3 |
3 files changed, 2 insertions, 4 deletions
diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h index 42aa4a22803c..ae5a0df5316e 100644 --- a/arch/arm/include/asm/uaccess.h +++ b/arch/arm/include/asm/uaccess.h @@ -59,7 +59,6 @@ extern int __put_user_bad(void); * Note that this is actually 0x1,0000,0000 */ #define KERNEL_DS 0x00000000 -#define get_ds() (KERNEL_DS) #ifdef CONFIG_MMU diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 16601d1442d1..72cc0862a30e 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -150,7 +150,7 @@ void __show_regs(struct pt_regs *regs) if ((domain & domain_mask(DOMAIN_USER)) == domain_val(DOMAIN_USER, DOMAIN_NOACCESS)) segment = "none"; - else if (fs == get_ds()) + else if (fs == KERNEL_DS) segment = "kernel"; else segment = "user"; diff --git a/arch/arm/xen/hypercall.S b/arch/arm/xen/hypercall.S index b0b80c0f09f3..b11bba542fac 100644 --- a/arch/arm/xen/hypercall.S +++ b/arch/arm/xen/hypercall.S @@ -113,8 +113,7 @@ ENTRY(privcmd_call) /* * Disable userspace access from kernel. This is fine to do it - * unconditionally as no set_fs(KERNEL_DS)/set_fs(get_ds()) is - * called before. + * unconditionally as no set_fs(KERNEL_DS) is called before. */ uaccess_disable r4 |