| From: |
| Josh Triplett <josh@joshtriplett.org> |
| To: |
| linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, x86@kernel.org, xen-devel@lists.xenproject.org |
| Subject: |
| [PATCH 0/3] x86: Support compiling out userspace I/O (iopl and ioperm) |
| Date: |
| Tue, 22 Oct 2013 03:33:58 +0100 |
| Message-ID: |
| <cover.1382407802.git.josh@joshtriplett.org> |
| Cc: |
| Alexander van Heukelum <heukelum@fastmail.fm>, Jeremy Fitzhardinge <jeremy@goop.org>, Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>, Len Brown <len.brown@intel.com>, Frederic Weisbecker <fweisbec@gmail.com>, "H. Peter Anvin" <hpa@zytor.com>, Paul Gortmaker <paul.gortmaker@windriver.com>, David Herrmann <dh.herrmann@gmail.com>, Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>, Seiji Aguchi <seiji.aguchi@hds.com>, Jiri Slaby <jslaby@suse.cz>, Alok Kataria <akataria@vmware.com>, Jesper Nilsson <jesper.nilsson@axis.com>, Andi Kleen <ak@linux.intel.com>, Daniel Lezcano <daniel.lezcano@linaro.org>, Ingo Molnar <mingo@redhat.com>, Steven Rostedt <rostedt@goodmis.org>, Borislav Petkov <bp@suse.de>, Fenghua Yu <fenghua.yu@intel.com>, Kees Cook <keescook@chromium.org>, Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>, Ross Lagerwall <rosslagerwall@gmail.com>, Chris Metca |
| Archive‑link: | |
Article |
This patch series makes it possible to compile out the iopl and ioperm system
calls, which allow privileged processes to request permission to directly poke
I/O ports from userspace.
Nothing on a modern Linux system uses these calls anymore, and anything new
should be using /dev/port instead, or better yet writing a driver.
Copying the bloat-o-meter stats from the final patch:
32-bit bloat-o-meter:
add/remove: 0/3 grow/shrink: 0/10 up/down: 0/-17681 (-17681)
function old new delta
cpu_init 676 668 -8
ioperm_active 18 7 -11
init_task 1296 1284 -12
exit_thread 179 91 -88
ioperm_get 103 10 -93
__switch_to_xtra 254 161 -93
sys_iopl 127 - -127
SyS_iopl 127 - -127
copy_thread 606 446 -160
vt_ioctl 4127 3919 -208
sys_ioperm 370 - -370
init_tss 8576 384 -8192
doublefault_tss 8576 384 -8192
64-bit bloat-o-meter:
add/remove: 0/4 grow/shrink: 2/9 up/down: 45/-9764 (-9719)
function old new delta
cpu_init 958 995 +37
arch_align_stack 78 86 +8
perf_event_exit_task 525 517 -8
ioperm_active 17 8 -9
init_task 1968 1944 -24
stub_iopl 81 - -81
ioperm_get 111 11 -100
__switch_to_xtra 281 164 -117
exit_thread 212 92 -120
vt_ioctl 4432 4304 -128
sys_iopl 137 - -137
SyS_iopl 137 - -137
copy_thread 694 520 -174
sys_ioperm 473 - -473
init_tss 8896 640 -8256
Josh Triplett (3):
x86: process: Unify 32-bit and 64-bit copy_thread I/O bitmap handling
x86: tss: Eliminate fragile calculation of TSS segment limit
x86: Support compiling out userspace I/O (iopl and ioperm)
arch/x86/Kconfig | 10 ++++
arch/x86/include/asm/desc.h | 11 +----
arch/x86/include/asm/paravirt.h | 2 +
arch/x86/include/asm/paravirt_types.h | 2 +
arch/x86/include/asm/processor.h | 54 +++++++++++++++++---
arch/x86/include/asm/syscalls.h | 3 ++
arch/x86/kernel/Makefile | 3 +-
arch/x86/kernel/cpu/common.c | 12 +----
arch/x86/kernel/entry_64.S | 9 ++--
arch/x86/kernel/paravirt.c | 2 +
arch/x86/kernel/process-io.h | 93 +++++++++++++++++++++++++++++++++++
arch/x86/kernel/process.c | 34 ++-----------
arch/x86/kernel/process_32.c | 40 ++++-----------
arch/x86/kernel/process_64.c | 26 ++--------
arch/x86/kernel/ptrace.c | 8 +++
arch/x86/xen/enlighten.c | 4 ++
drivers/tty/vt/vt_ioctl.c | 2 +-
kernel/sys_ni.c | 5 ++
18 files changed, 206 insertions(+), 114 deletions(-)
create mode 100644 arch/x86/kernel/process-io.h
--
1.8.4.rc3