ARM: 9113/1: uaccess: remove set_fs() implementation

There are no remaining callers of set_fs(), so just remove it
along with all associated code that operates on
thread_info->addr_limit.

There are still further optimizations that can be done:

- In get_user(), the address check could be moved entirely
  into the out of line code, rather than passing a constant
  as an argument,

- I assume the DACR handling can be simplified as we now
  only change it during user access when CONFIG_CPU_SW_DOMAIN_PAN
  is set, but not during set_fs().

Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

1 files changed, 1 insertions, 6 deletions

diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
index fc9e8b37eaa8..581542fbf5bf 100644
--- a/arch/arm/kernel/process.c
+++ b/arch/arm/kernel/process.c
@@ -108,7 +108,7 @@ void __show_regs(struct pt_regs *regs)
 	unsigned long flags;
 	char buf[64];
 #ifndef CONFIG_CPU_V7M
-	unsigned int domain, fs;
+	unsigned int domain;
 #ifdef CONFIG_CPU_SW_DOMAIN_PAN
 	/*
 	 * Get the domain register for the parent context. In user
@@ -117,14 +117,11 @@ void __show_regs(struct pt_regs *regs)
 	 */
 	if (user_mode(regs)) {
 		domain = DACR_UACCESS_ENABLE;
-		fs = get_fs();
 	} else {
 		domain = to_svc_pt_regs(regs)->dacr;
-		fs = to_svc_pt_regs(regs)->addr_limit;
 	}
 #else
 	domain = get_domain();
-	fs = get_fs();
 #endif
 #endif
 
@@ -160,8 +157,6 @@ void __show_regs(struct pt_regs *regs)
 		if ((domain & domain_mask(DOMAIN_USER)) ==
 		    domain_val(DOMAIN_USER, DOMAIN_NOACCESS))
 			segment = "none";
-		else if (fs == KERNEL_DS)
-			segment = "kernel";
 		else
 			segment = "user";