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-rw-r--r--arch/mips/kernel/syscall.c9
1 files changed, 8 insertions, 1 deletions
diff --git a/arch/mips/kernel/syscall.c b/arch/mips/kernel/syscall.c
index af1bdc897488..3523c8d12eda 100644
--- a/arch/mips/kernel/syscall.c
+++ b/arch/mips/kernel/syscall.c
@@ -40,7 +40,14 @@
#include <asm/sysmips.h>
#include <asm/uaccess.h>
-asmlinkage int sys_pipe(nabi_no_regargs volatile struct pt_regs regs)
+/*
+ * For historic reasons the pipe(2) syscall on MIPS has an unusual calling
+ * convention. It returns results in registers $v0 / $v1 which means there
+ * is no need for it to do verify the validity of a userspace pointer
+ * argument. Historically that used to be expensive in Linux. These days
+ * the performance advantage is negligible.
+ */
+asmlinkage int sysm_pipe(nabi_no_regargs volatile struct pt_regs regs)
{
int fd[2];
int error, res;
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