linux/arch/x86/kernel
Luis R. Rodriguez cb32edf65b x86/mm/pat: Wrap pat_enabled into a function API
We use pat_enabled in x86-specific code to see if PAT is enabled
or not but we're granting full access to it even though readers
do not need to set it. If, for instance, we granted access to it
to modules later they then could override the variable
setting... no bueno.

This renames pat_enabled to a new static variable __pat_enabled.
Folks are redirected to use pat_enabled() now.

Code that sets this can only be internal to pat.c. Apart from
the early kernel parameter "nopat" to disable PAT, we also have
a few cases that disable it later and make use of a helper
pat_disable(). It is wrapped under an ifdef but since that code
cannot run unless PAT was enabled its not required to wrap it
with ifdefs, unwrap that. Likewise, since "nopat" doesn't really
change non-PAT systems just remove that ifdef as well.

Although we could add and use an early_param_off(), these
helpers don't use __read_mostly but we want to keep
__read_mostly for __pat_enabled as this is a hot path -- upon
boot, for instance, a simple guest may see ~4k accesses to
pat_enabled(). Since __read_mostly early boot params are not
that common we don't add a helper for them just yet.

Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Walls <awalls@md.metrocast.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Doug Ledford <dledford@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kyle McMartin <kyle@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1430425520-22275-3-git-send-email-mcgrof@do-not-panic.com
Link: http://lkml.kernel.org/r/1432628901-18044-13-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-27 14:41:01 +02:00
..
acpi Initial ACPI support for arm64: 2015-04-24 08:23:45 -07:00
apic This is the final removal (after several years!) of the obsolete cpus_* 2015-04-20 10:19:03 -07:00
cpu x86/mm/pat: Wrap pat_enabled into a function API 2015-05-27 14:41:01 +02:00
kprobes Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-04-14 14:37:47 -07:00
.gitignore
Makefile Merge branch 'x86-pmem-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-04-18 11:42:49 -04:00
alternative.c x86/alternatives: Guard NOPs optimization 2015-04-06 09:24:09 +02:00
amd_gart_64.c x86: enable DMA CMA with swiotlb 2014-06-04 16:53:57 -07:00
amd_nb.c x86, amd_nb: Add device IDs to NB tables for F15h M60h 2014-10-20 14:18:45 +02:00
apb_timer.c x86/platform: Remove unused function from apb_timer.c 2014-12-23 10:43:35 +01:00
aperture_64.c x86/gart: Tidy messages and add bridge device info 2014-05-23 10:47:19 -06:00
apm_32.c cpuidle: Invert CPUIDLE_FLAG_TIME_VALID logic 2014-11-12 21:17:27 +01:00
asm-offsets.c sched, x86: Provide a per-cpu preempt_count implementation 2013-09-25 14:07:57 +02:00
asm-offsets_32.c x86/asm/entry/32: Document the 32-bit SYSENTER "emergency stack" better 2015-03-17 09:25:29 +01:00
asm-offsets_64.c x86/asm/entry/64/compat: Change the 32-bit sysenter code to use sp0 2015-03-06 08:32:58 +01:00
audit_64.c x86: hook up execveat system call 2014-12-13 12:42:51 -08:00
bootflag.c
check.c x86/mm: memblock: switch to use NUMA_NO_NODE 2014-01-21 16:19:47 -08:00
cpuid.c x86, cpuid: Use PTR_ERR_OR_ZERO 2014-10-17 13:40:51 -07:00
crash.c x86/asm/entry: Change all 'user_mode_vm()' calls to 'user_mode()' 2015-03-23 11:14:17 +01:00
crash_dump_32.c
crash_dump_64.c
devicetree.c x86/mm: Use early_memunmap() instead of early_iounmap() 2015-02-24 15:58:06 +01:00
doublefault.c x86: Delete non-required instances of include <linux/init.h> 2014-01-06 21:25:18 -08:00
dumpstack.c Merge branch 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-04-13 13:23:34 -07:00
dumpstack_32.c Merge branch 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-04-13 13:23:34 -07:00
dumpstack_64.c x86/kernel: Use kstack_end() in dumpstack_64.c 2015-02-23 18:37:13 +01:00
e820.c Merge branch 'x86-pmem-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-04-18 11:42:49 -04:00
early-quirks.c drm/i915/skl: Add the additional graphics stolen sizes 2014-09-24 14:47:39 +02:00
early_printk.c TTY/Serial patches for 4.1-rc1 2015-04-21 09:33:10 -07:00
entry_32.S x86/asm/entry/32: Tidy up JNZ instructions after TESTs 2015-04-11 10:40:02 +02:00
entry_64.S x86_64, asm: Work around AMD SYSRET SS descriptor attribute issue 2015-04-26 17:57:38 -07:00
espfix_64.c x86, espfix: Remove stale ptemask 2014-11-11 17:57:46 +01:00
ftrace.c module: remove mod arg from module_free, rename module_memfree(). 2015-01-20 11:38:33 +10:30
head.c x86: Make sure we can boot in the case the BDA contains pure garbage 2013-02-27 13:38:57 -08:00
head32.c x86: Store a per-cpu shadow copy of CR4 2015-02-04 12:10:42 +01:00
head64.c Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-04-13 13:19:10 -07:00
head_32.S x86/asm/boot: Use already defined KEEP_SEGMENTS macro in head_{32,64}.S 2015-02-19 10:05:04 +01:00
head_64.S x86/asm: Optimize unnecessarily wide TEST instructions 2015-03-07 11:12:43 +01:00
hpet.c kernel.h: remove ancient __FUNCTION__ hack 2015-02-12 18:54:13 -08:00
hw_breakpoint.c perf/x86: Remove get_hbp_len and replace with bp_len 2014-12-03 15:14:30 +01:00
i386_ksyms_32.c sched, x86: Optimize the preempt_schedule() call 2013-09-25 14:23:07 +02:00
i387.c x86/fpu: Load xsave pointer *after* initialization 2015-04-17 10:15:47 +02:00
i8237.c
i8253.c
i8259.c x86/irq: Fix XT-PIC-XT-PIC in /proc/interrupts 2014-10-28 12:01:08 +01:00
io_delay.c
ioport.c x86/asm/entry: Rename 'init_tss' to 'cpu_tss' 2015-03-06 08:32:58 +01:00
iosf_mbi.c x86/platform/intel/iosf: Add debugfs config option for IOSF 2014-09-19 13:08:43 +02:00
irq.c x86: fix up obsolete cpu function usage. 2015-03-05 15:25:05 +10:30
irq_32.c x86/asm/entry: Change all 'user_mode_vm()' calls to 'user_mode()' 2015-03-23 11:14:17 +01:00
irq_64.c x86/asm/entry: Change all 'user_mode_vm()' calls to 'user_mode()' 2015-03-23 11:14:17 +01:00
irq_work.c x86: Tell irq work about self IPI support 2014-09-13 18:38:29 +02:00
irqinit.c x86/asm/entry/irq: Simplify interrupt dispatch table (IDT) layout 2015-04-08 09:02:13 +02:00
jump_label.c x86/jump_label: expect default_nop if static_key gets enabled on boot-up 2013-10-19 19:45:35 -04:00
kdebugfs.c
kexec-bzimage64.c kexec-bzimage64: fix sparse warnings 2014-10-14 02:18:21 +02:00
kgdb.c Linux 4.0-rc7 2015-04-08 09:01:54 +02:00
ksysfs.c x86: ksysfs.c build fix 2014-01-03 14:37:13 +00:00
kvm.c watchdog: introduce the hardlockup_detector_disable() function 2015-04-14 16:48:59 -07:00
kvmclock.c x86, kvm: Clear paravirt_enabled on KVM guests for espfix32's benefit 2014-12-10 12:49:39 +01:00
ldt.c Revert "x86-64, modify_ldt: Make support for 16-bit segments a runtime option" 2014-05-21 10:22:59 -07:00
livepatch.c livepatch: kernel: add support for live patching 2014-12-22 15:40:49 +01:00
machine_kexec_32.c x86, irq: Move IOAPIC related declarations from hw_irq.h into io_apic.h 2014-12-16 14:08:17 +01:00
machine_kexec_64.c x86, irq: Move IOAPIC related declarations from hw_irq.h into io_apic.h 2014-12-16 14:08:17 +01:00
mcount_64.S ftrace/fgraph/x86: Have prepare_ftrace_return() take ip as first parameter 2014-12-01 14:08:58 -05:00
mmconf-fam10h_64.c x86: delete __cpuinit usage from all x86 files 2013-07-14 19:36:56 -04:00
module.c x86/mm/KASLR: Propagate KASLR status to kernel proper 2015-04-03 15:26:15 +02:00
mpparse.c x86, apic: Remove mps_oem_check callback 2014-07-31 08:05:42 -07:00
msr.c x86, msr: Use seek definitions instead of hard-coded values 2014-10-17 13:40:55 -07:00
nmi.c kprobes, x86: Use NOKPROBE_SYMBOL() instead of __kprobes annotation 2014-04-24 10:26:38 +02:00
nmi_selftest.c
paravirt-spinlocks.c x86, ticketlock: Add slowpath logic 2013-08-09 07:54:00 -07:00
paravirt.c x86: expose number of page table levels on Kconfig level 2015-04-14 16:49:02 -07:00
paravirt_patch_32.c
paravirt_patch_64.c x86_64/entry/xen: Do not invoke espfix64 on Xen 2014-07-28 15:25:40 -07:00
pci-calgary_64.c x86, calgary: Use 8M TCE table size by default 2014-04-10 19:51:32 -07:00
pci-dma.c arch/x86/kernel/pci-dma.c: fix dma_generic_alloc_coherent() when CONFIG_DMA_CMA is enabled 2014-06-04 16:53:57 -07:00
pci-iommu_table.c
pci-nommu.c x86: Delete non-required instances of include <linux/init.h> 2014-01-06 21:25:18 -08:00
pci-swiotlb.c x86: enable DMA CMA with swiotlb 2014-06-04 16:53:57 -07:00
pcspeaker.c
perf_regs.c perf/x86/64: Report regs_user->ax too in get_regs_user() 2015-04-11 13:08:53 +02:00
pmc_atom.c x86: pmc_atom: Expose contents of PSS 2015-01-20 12:50:14 +01:00
pmem.c x86/mm: Add support for the non-standard protected e820 type 2015-04-01 17:02:43 +02:00
probe_roms.c
process.c x86/fpu: Always restore_xinit_state() when use_eager_cpu() 2015-05-06 11:22:03 +02:00
process_32.c x86/asm/entry: Get rid of KERNEL_STACK_OFFSET 2015-03-24 19:42:38 +01:00
process_64.c x86_64, asm: Work around AMD SYSRET SS descriptor attribute issue 2015-04-26 17:57:38 -07:00
ptrace.c x86/asm/entry: Change all 'user_mode_vm()' calls to 'user_mode()' 2015-03-23 11:14:17 +01:00
pvclock.c x86: pvclock: Really remove the sched notifier for cross-cpu migrations 2015-04-27 15:49:30 +02:00
quirks.c x86: HPET force enable for e6xx based systems 2014-09-15 17:53:35 -07:00
reboot.c x86/reboot: Add ASRock Q1900DC-ITX mainboard reboot quirk 2015-04-01 14:08:09 +02:00
reboot_fixups_32.c
relocate_kernel_32.S x86/asm: Optimize unnecessarily wide TEST instructions 2015-03-07 11:12:43 +01:00
relocate_kernel_64.S x86/asm: Replace "MOVQ $imm, %reg" with MOVL 2015-04-01 13:17:39 +02:00
resource.c x86: don't exclude low BIOS area when allocating address space for non-PCI cards 2014-07-16 12:29:36 -06:00
rtc.c kernel.h: remove ancient __FUNCTION__ hack 2015-02-12 18:54:13 -08:00
setup.c Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-04-13 13:31:32 -07:00
setup_percpu.c x86: Convert a few more per-CPU items to read-mostly ones 2014-11-04 20:13:28 +01:00
signal.c Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-04-18 11:31:11 -04:00
smp.c asmlinkage, x86: Add explicit __visible to arch/x86/* 2014-05-05 16:07:44 -07:00
smpboot.c Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-04-14 13:36:04 -07:00
stacktrace.c
step.c ptrace: ensure arch_ptrace/ptrace_request can never race with SIGKILL 2013-01-22 10:08:00 -08:00
sys_x86_64.c x86/mm: Improve AMD Bulldozer ASLR workaround 2015-03-31 10:01:17 +02:00
syscall_32.c x86/compat: Merge native and compat 32-bit syscall tables 2015-03-04 06:16:21 +01:00
syscall_64.c x86, asmlinkage: Make syscall tables visible 2013-08-06 14:20:18 -07:00
sysfb.c x86/sysfb: Use PTR_ERR_OR_ZERO 2014-10-17 13:40:52 -07:00
sysfb_efi.c x86: sysfb: move EFI quirks from efifb to sysfb 2013-08-02 16:17:47 -07:00
sysfb_simplefb.c x86/simplefb: Use PTR_ERR_OR_ZERO 2014-10-17 13:40:52 -07:00
tboot.c x86 / tboot / ACPI: Fail extended mode reduced hardware sleep 2013-07-31 14:25:51 +02:00
tce_64.c
test_nx.c
test_rodata.c treewide: Fix typo in printk messages 2015-03-06 23:05:39 +01:00
time.c x86/asm/entry: Change all 'user_mode_vm()' calls to 'user_mode()' 2015-03-23 11:14:17 +01:00
tls.c x86, tls: Interpret an all-zero struct user_desc as "no segment" 2015-01-22 21:45:07 +01:00
tls.h
topology.c hotplug, powerpc, x86: Remove cpu_hotplug_driver_lock() 2013-09-30 19:55:51 +02:00
trace_clock.c tracing,x86: Add a TSC trace_clock 2012-11-13 15:48:27 -05:00
tracepoint.c x86: Make sure IDT is page aligned 2013-07-16 15:14:48 -07:00
traps.c Merge branch 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-04-14 13:58:48 -07:00
tsc.c x86/tsc: Change Fast TSC calibration failed from error to info 2015-01-23 10:53:52 +01:00
tsc_msr.c x86: tsc: Add missing Baytrail frequency to the table 2014-02-19 17:12:24 +01:00
tsc_sync.c x86: Delete non-required instances of include <linux/init.h> 2014-01-06 21:25:18 -08:00
uprobes.c x86/asm/entry: Change all 'user_mode_vm()' calls to 'user_mode()' 2015-03-23 11:14:17 +01:00
verify_cpu.S
vm86_32.c x86/asm/entry: Rename 'init_tss' to 'cpu_tss' 2015-03-06 08:32:58 +01:00
vmlinux.lds.S x86-64: Use RIP-relative addressing for most per-CPU accesses 2014-11-04 20:43:14 +01:00
vsmp_64.c x86/apic/vsmp: Make is_vsmp_box() static 2014-08-01 15:09:45 -07:00
vsyscall_64.c x86_64/vsyscall: Restore orig_ax after vsyscall seccomp 2014-11-10 10:46:35 +01:00
vsyscall_emu_64.S
vsyscall_gtod.c time: Rename timekeeper::tkr to timekeeper::tkr_mono 2015-03-27 09:45:06 +01:00
vsyscall_trace.h
x86_init.c Revert "PCI: Add x86_msi.msi_mask_irq() and msix_mask_irq()" 2014-11-11 15:14:30 -07:00
x8664_ksyms_64.c x86_64: kasan: add interceptors for memset/memmove/memcpy functions 2015-02-13 21:21:41 -08:00
xsave.c x86/fpu: Kill eager_fpu_init_bp() 2015-03-23 10:14:00 +01:00