From feb9ef384895f34badad70d6a0eb219d7bc0c4df Mon Sep 17 00:00:00 2001 From: Michael Kerrisk Date: Mon, 29 Jun 2020 13:46:00 +0200 Subject: [PATCH] iopl.2: Minor tweaks to Thomas Piekarski's patch Signed-off-by: Michael Kerrisk --- man2/iopl.2 | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/man2/iopl.2 b/man2/iopl.2 index be9acfd1e..1f82b0182 100644 --- a/man2/iopl.2 +++ b/man2/iopl.2 @@ -46,10 +46,11 @@ as specified by the two least significant bits in The I/O privilege level for a normal thread is 0. Permissions are inherited from parents to children. .PP -This call is deprecated, significantly slower than -.BR ioperm(2) +This call is deprecated, is significantly slower than +.BR ioperm (2), and is only provided for older X servers which require -access to all 65536 I/O ports. It is mostly for the i386 architecture. +access to all 65536 I/O ports. +It is mostly for the i386 architecture. On many other architectures it does not exist or will always return an error. .SH RETURN VALUE @@ -90,8 +91,8 @@ Avoid the latter, it is available on i386 only. Prior to Linux 5.5 .BR iopl () allowed the thread to disable interrupts while running -at a higher I/O privilege level. This will probably crash -the system, and is not recommended. +at a higher I/O privilege level. +This will probably crash the system, and is not recommended. .PP Prior to Linux 3.7, on some architectures (such as i386), permissions