linux/arch/x86
Ricardo Neri fd11a6496e x86/umip: Print a warning into the syslog if UMIP-protected instructions are used
Print a rate-limited warning when a user-space program attempts to execute
any of the instructions that UMIP protects (i.e., SGDT, SIDT, SLDT, STR
and SMSW).

This is useful, because when CONFIG_X86_INTEL_UMIP=y is selected and
supported by the hardware, user space programs that try to execute such
instructions will receive a SIGSEGV signal that they might not expect.

In the specific cases for which emulation is provided (instructions SGDT,
SIDT and SMSW in protected and virtual-8086 modes), no signal is
generated. However, a warning is helpful to encourage updates in such
programs to avoid the use of such instructions.

Warnings are printed via a customized printk() function that also provides
information about the program that attempted to use the affected
instructions.

Utility macros are defined to wrap umip_printk() for the error and warning
kernel log levels.

While here, replace an existing call to the generic rate-limited pr_err()
with the new umip_pr_err().

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi V. Shankar <ravi.v.shankar@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: ricardo.neri@intel.com
Link: http://lkml.kernel.org/r/1511233476-17088-1-git-send-email-ricardo.neri-calderon@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-21 08:13:43 +01:00
..
boot Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 16:58:05 -08:00
configs x86/unwind: Rename unwinder config options to 'CONFIG_UNWINDER_*' 2017-10-14 10:12:12 +02:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2017-11-06 09:05:03 -08:00
entry Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 16:58:05 -08:00
events perf/x86/intel/uncore: Cache logical pkg id in uncore driver 2017-11-17 16:22:30 +01:00
hyperv x86/virt: Add enum for hypervisors to replace x86_hyper 2017-11-10 10:03:12 +01:00
ia32 License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
include x86/topology: Avoid wasting 128k for package id array 2017-11-17 16:22:30 +01:00
kernel x86/umip: Print a warning into the syslog if UMIP-protected instructions are used 2017-11-21 08:13:43 +01:00
kvm Merge branch 'linus' into locking/core, to resolve conflicts 2017-11-07 10:32:44 +01:00
lib Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 14:13:48 -08:00
math-emu License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mm x86/mm: Limit mmap() of /dev/mem to valid physical addresses 2017-11-16 12:49:48 +01:00
net bpf: fix bpf_tail_call() x64 JIT 2017-10-03 16:04:44 -07:00
oprofile x86/oprofile/ppro: Do not use __this_cpu*() in preemptible context 2017-11-08 13:01:54 +01:00
pci License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
platform Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 17:33:11 -08:00
power License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
purgatory License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ras License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
realmode x86/realmode: Don't decrypt trampoline area under SEV 2017-11-07 15:35:55 +01:00
tools License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
um Merge branch 'linus' into x86/asm, to pick up fixes and resolve conflicts 2017-11-07 10:53:06 +01:00
video
xen Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 18:29:23 -08:00
.gitignore
Kbuild Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-09-07 09:25:15 -07:00
Kconfig x86/umip: Select X86_INTEL_UMIP by default 2017-11-14 08:38:08 +01:00
Kconfig.cpu License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Kconfig.debug Merge branch 'linus' into x86/asm, to pick up fixes and resolve conflicts 2017-11-07 10:53:06 +01:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Makefile_32.cpu License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Makefile.um License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00