linux_dsm_epyc7002/arch/x86/kernel
Ingo Molnar 2e85591a6c x86/fpu: Better document fpu__clear() state handling
So prior to this fix:

  c88d47480d ("x86/fpu: Always restore_xinit_state() when use_eager_cpu()")

we leaked FPU state across execve() boundaries on eagerfpu systems:

	$ /host/home/mingo/dump-xmm-regs-exec
	# XMM state before execve():
	XMM0 : 000000000000dede
	XMM1 : 000000000000dedf
	XMM2 : 000000000000dee0
	XMM3 : 000000000000dee1
	XMM4 : 000000000000dee2
	XMM5 : 000000000000dee3
	XMM6 : 000000000000dee4
	XMM7 : 000000000000dee5
	XMM8 : 000000000000dee6
	XMM9 : 000000000000dee7
	XMM10: 000000000000dee8
	XMM11: 000000000000dee9
	XMM12: 000000000000deea
	XMM13: 000000000000deeb
	XMM14: 000000000000deec
	XMM15: 000000000000deed

	# XMM state after execve(), in the new task context:
	XMM0 : 0000000000000000
	XMM1 : 2f2f2f2f2f2f2f2f
	XMM2 : 0000000000000000
	XMM3 : 0000000000000000
	XMM4 : 00000000000000ff
	XMM5 : 00000000ff000000
	XMM6 : 000000000000dee4
	XMM7 : 000000000000dee5
	XMM8 : 0000000000000000
	XMM9 : 0000000000000000
	XMM10: 0000000000000000
	XMM11: 0000000000000000
	XMM12: 0000000000000000
	XMM13: 000000000000deeb
	XMM14: 000000000000deec
	XMM15: 000000000000deed

Better explain what this function is supposed to do and why.

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 15:48:02 +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/fpu: Move various internal function prototypes to fpu/internal.h 2015-05-19 15:47:48 +02:00
fpu x86/fpu: Better document fpu__clear() state handling 2015-05-19 15:48:02 +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
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_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
asm-offsets.c sched, x86: Provide a per-cpu preempt_count implementation 2013-09-25 14:07:57 +02:00
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_dump_32.c
crash_dump_64.c
crash.c x86/asm/entry: Change all 'user_mode_vm()' calls to 'user_mode()' 2015-03-23 11:14:17 +01:00
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_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
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
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_printk.c TTY/Serial patches for 4.1-rc1 2015-04-21 09:33:10 -07:00
early-quirks.c drm/i915/skl: Add the additional graphics stolen sizes 2014-09-24 14:47:39 +02:00
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
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
head.c x86: Make sure we can boot in the case the BDA contains pure garbage 2013-02-27 13:38:57 -08:00
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
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_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
irq.c x86: fix up obsolete cpu function usage. 2015-03-05 15:25:05 +10:30
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
Makefile x86/fpu: Move i387.c and xsave.c to arch/x86/kernel/fpu/ 2015-05-19 15:47:15 +02:00
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_selftest.c
nmi.c kprobes, x86: Use NOKPROBE_SYMBOL() instead of __kprobes annotation 2014-04-24 10:26:38 +02:00
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
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
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_32.c x86/fpu: Rename fpu-internal.h to fpu/internal.h 2015-05-19 15:47:31 +02:00
process_64.c x86/fpu: Rename fpu-internal.h to fpu/internal.h 2015-05-19 15:47:31 +02:00
process.c x86/fpu: Remove failure paths from fpstate-alloc low level functions 2015-05-19 15:47:50 +02:00
ptrace.c x86/fpu: Rename regset FPU register accessors 2015-05-19 15:47:35 +02:00
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_fixups_32.c
reboot.c x86/reboot: Add ASRock Q1900DC-ITX mainboard reboot quirk 2015-04-01 14:08:09 +02:00
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_percpu.c x86: Convert a few more per-CPU items to read-mostly ones 2014-11-04 20:13:28 +01:00
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
signal.c x86/fpu: Rename save_xstate_sig() to copy_fpstate_to_sigframe() 2015-05-19 15:48:01 +02:00
smp.c asmlinkage, x86: Add explicit __visible to arch/x86/* 2014-05-05 16:07:44 -07:00
smpboot.c x86/fpu: Rename fpu-internal.h to fpu/internal.h 2015-05-19 15:47:31 +02:00
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_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
sysfb.c x86/sysfb: 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 x86/fpu: Simplify FPU handling by embedding the fpstate in task_struct (again) 2015-05-19 15:47:49 +02:00
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
tsc.c x86/tsc: Change Fast TSC calibration failed from error to info 2015-01-23 10:53:52 +01:00
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