From: Andy Lutomirski <luto@xxxxxxxxxxxxxx> This patch has been added to the 3.18 stable tree. If you have any objections, please let us know. =============== [ Upstream commit 375074cc736ab1d89a708c0a8d7baa4a70d5d476 ] CR4 manipulation was split, seemingly at random, between direct (write_cr4) and using a helper (set/clear_in_cr4). Unfortunately, the set_in_cr4 and clear_in_cr4 helpers also poke at the boot code, which only a small subset of users actually wanted. This patch replaces all cr4 access in functions that don't leave cr4 exactly the way they found it with new helpers cr4_set_bits, cr4_clear_bits, and cr4_set_bits_and_update_boot. Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxxxxxx> Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx> Cc: Vince Weaver <vince@xxxxxxxxxx> Cc: "hillf.zj" <hillf.zj@xxxxxxxxxxxxxxx> Cc: Valdis Kletnieks <Valdis.Kletnieks@xxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Cc: Kees Cook <keescook@xxxxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/495a10bdc9e67016b8fd3945700d46cfd5c12c2f.1414190806.git.luto@xxxxxxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx> --- arch/x86/include/asm/processor.h | 33 -------------------------------- arch/x86/include/asm/tlbflush.h | 37 ++++++++++++++++++++++++++++++++++++ arch/x86/include/asm/virtext.h | 3 ++- arch/x86/kernel/cpu/common.c | 10 +++++----- arch/x86/kernel/cpu/mcheck/mce.c | 3 ++- arch/x86/kernel/cpu/mcheck/p5.c | 3 ++- arch/x86/kernel/cpu/mcheck/winchip.c | 3 ++- arch/x86/kernel/cpu/perf_event.c | 7 ++++--- arch/x86/kernel/i387.c | 3 ++- arch/x86/kernel/process.c | 5 +++-- arch/x86/kernel/xsave.c | 3 ++- arch/x86/kvm/vmx.c | 4 ++-- arch/x86/mm/init.c | 4 ++-- arch/x86/xen/enlighten.c | 4 ++-- drivers/lguest/x86/core.c | 5 +++-- 15 files changed, 70 insertions(+), 57 deletions(-) diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index eb71ec7..ddd8d13 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -578,39 +578,6 @@ static inline void load_sp0(struct tss_struct *tss, #define set_iopl_mask native_set_iopl_mask #endif /* CONFIG_PARAVIRT */ -/* - * Save the cr4 feature set we're using (ie - * Pentium 4MB enable and PPro Global page - * enable), so that any CPU's that boot up - * after us can get the correct flags. - */ -extern unsigned long mmu_cr4_features; -extern u32 *trampoline_cr4_features; - -static inline void set_in_cr4(unsigned long mask) -{ - unsigned long cr4; - - mmu_cr4_features |= mask; - if (trampoline_cr4_features) - *trampoline_cr4_features = mmu_cr4_features; - cr4 = read_cr4(); - cr4 |= mask; - write_cr4(cr4); -} - -static inline void clear_in_cr4(unsigned long mask) -{ - unsigned long cr4; - - mmu_cr4_features &= ~mask; - if (trampoline_cr4_features) - *trampoline_cr4_features = mmu_cr4_features; - cr4 = read_cr4(); - cr4 &= ~mask; - write_cr4(cr4); -} - typedef struct { unsigned long seg; } mm_segment_t; diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h index 04905bf..fc0c4bc 100644 --- a/arch/x86/include/asm/tlbflush.h +++ b/arch/x86/include/asm/tlbflush.h @@ -15,6 +15,43 @@ #define __flush_tlb_single(addr) __native_flush_tlb_single(addr) #endif +/* Set in this cpu's CR4. */ +static inline void cr4_set_bits(unsigned long mask) +{ + unsigned long cr4; + + cr4 = read_cr4(); + cr4 |= mask; + write_cr4(cr4); +} + +/* Clear in this cpu's CR4. */ +static inline void cr4_clear_bits(unsigned long mask) +{ + unsigned long cr4; + + cr4 = read_cr4(); + cr4 &= ~mask; + write_cr4(cr4); +} + +/* + * Save some of cr4 feature set we're using (e.g. Pentium 4MB + * enable and PPro Global page enable), so that any CPU's that boot + * up after us can get the correct flags. This should only be used + * during boot on the boot cpu. + */ +extern unsigned long mmu_cr4_features; +extern u32 *trampoline_cr4_features; + +static inline void cr4_set_bits_and_update_boot(unsigned long mask) +{ + mmu_cr4_features |= mask; + if (trampoline_cr4_features) + *trampoline_cr4_features = mmu_cr4_features; + cr4_set_bits(mask); +} + static inline void __native_flush_tlb(void) { native_write_cr3(native_read_cr3()); diff --git a/arch/x86/include/asm/virtext.h b/arch/x86/include/asm/virtext.h index 5da71c2..f41e19c 100644 --- a/arch/x86/include/asm/virtext.h +++ b/arch/x86/include/asm/virtext.h @@ -19,6 +19,7 @@ #include <asm/vmx.h> #include <asm/svm.h> +#include <asm/tlbflush.h> /* * VMX functions: @@ -40,7 +41,7 @@ static inline int cpu_has_vmx(void) static inline void cpu_vmxoff(void) { asm volatile (ASM_VMX_VMXOFF : : : "cc"); - write_cr4(read_cr4() & ~X86_CR4_VMXE); + cr4_clear_bits(X86_CR4_VMXE); } static inline int cpu_vmx_enabled(void) diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index cfa9b5b..c230ed4 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -278,7 +278,7 @@ __setup("nosmep", setup_disable_smep); static __always_inline void setup_smep(struct cpuinfo_x86 *c) { if (cpu_has(c, X86_FEATURE_SMEP)) - set_in_cr4(X86_CR4_SMEP); + cr4_set_bits(X86_CR4_SMEP); } static __init int setup_disable_smap(char *arg) @@ -298,9 +298,9 @@ static __always_inline void setup_smap(struct cpuinfo_x86 *c) if (cpu_has(c, X86_FEATURE_SMAP)) { #ifdef CONFIG_X86_SMAP - set_in_cr4(X86_CR4_SMAP); + cr4_set_bits(X86_CR4_SMAP); #else - clear_in_cr4(X86_CR4_SMAP); + cr4_clear_bits(X86_CR4_SMAP); #endif } } @@ -1322,7 +1322,7 @@ void cpu_init(void) pr_debug("Initializing CPU#%d\n", cpu); - clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE); + cr4_clear_bits(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE); /* * Initialize the per-CPU GDT with the boot GDT, @@ -1403,7 +1403,7 @@ void cpu_init(void) printk(KERN_INFO "Initializing CPU#%d\n", cpu); if (cpu_feature_enabled(X86_FEATURE_VME) || cpu_has_tsc || cpu_has_de) - clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE); + cr4_clear_bits(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE); load_current_idt(); switch_to_new_gdt(cpu); diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c index b5c2276..bf44e45 100644 --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -43,6 +43,7 @@ #include <linux/export.h> #include <asm/processor.h> +#include <asm/tlbflush.h> #include <asm/mce.h> #include <asm/msr.h> @@ -1460,7 +1461,7 @@ static void __mcheck_cpu_init_generic(void) bitmap_fill(all_banks, MAX_NR_BANKS); machine_check_poll(MCP_UC | m_fl, &all_banks); - set_in_cr4(X86_CR4_MCE); + cr4_set_bits(X86_CR4_MCE); rdmsrl(MSR_IA32_MCG_CAP, cap); if (cap & MCG_CTL_P) diff --git a/arch/x86/kernel/cpu/mcheck/p5.c b/arch/x86/kernel/cpu/mcheck/p5.c index a304298..30692ac 100644 --- a/arch/x86/kernel/cpu/mcheck/p5.c +++ b/arch/x86/kernel/cpu/mcheck/p5.c @@ -8,6 +8,7 @@ #include <linux/smp.h> #include <asm/processor.h> +#include <asm/tlbflush.h> #include <asm/mce.h> #include <asm/msr.h> @@ -59,7 +60,7 @@ void intel_p5_mcheck_init(struct cpuinfo_x86 *c) "Intel old style machine check architecture supported.\n"); /* Enable MCE: */ - set_in_cr4(X86_CR4_MCE); + cr4_set_bits(X86_CR4_MCE); printk(KERN_INFO "Intel old style machine check reporting enabled on CPU#%d.\n", smp_processor_id()); diff --git a/arch/x86/kernel/cpu/mcheck/winchip.c b/arch/x86/kernel/cpu/mcheck/winchip.c index 7dc5564..590cc75 100644 --- a/arch/x86/kernel/cpu/mcheck/winchip.c +++ b/arch/x86/kernel/cpu/mcheck/winchip.c @@ -7,6 +7,7 @@ #include <linux/types.h> #include <asm/processor.h> +#include <asm/tlbflush.h> #include <asm/mce.h> #include <asm/msr.h> @@ -31,7 +32,7 @@ void winchip_mcheck_init(struct cpuinfo_x86 *c) lo &= ~(1<<4); /* Enable MCE */ wrmsr(MSR_IDT_FCR1, lo, hi); - set_in_cr4(X86_CR4_MCE); + cr4_set_bits(X86_CR4_MCE); printk(KERN_INFO "Winchip machine check reporting enabled on CPU#0.\n"); diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c index 143e5f5..6b5acd5 100644 --- a/arch/x86/kernel/cpu/perf_event.c +++ b/arch/x86/kernel/cpu/perf_event.c @@ -31,6 +31,7 @@ #include <asm/nmi.h> #include <asm/smp.h> #include <asm/alternative.h> +#include <asm/tlbflush.h> #include <asm/timer.h> #include <asm/desc.h> #include <asm/ldt.h> @@ -1328,7 +1329,7 @@ x86_pmu_notifier(struct notifier_block *self, unsigned long action, void *hcpu) case CPU_STARTING: if (x86_pmu.attr_rdpmc) - set_in_cr4(X86_CR4_PCE); + cr4_set_bits(X86_CR4_PCE); if (x86_pmu.cpu_starting) x86_pmu.cpu_starting(cpu); break; @@ -1834,9 +1835,9 @@ static void change_rdpmc(void *info) bool enable = !!(unsigned long)info; if (enable) - set_in_cr4(X86_CR4_PCE); + cr4_set_bits(X86_CR4_PCE); else - clear_in_cr4(X86_CR4_PCE); + cr4_clear_bits(X86_CR4_PCE); } static ssize_t set_attr_rdpmc(struct device *cdev, diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c index ae0fdc8..8d6e954 100644 --- a/arch/x86/kernel/i387.c +++ b/arch/x86/kernel/i387.c @@ -13,6 +13,7 @@ #include <asm/sigcontext.h> #include <asm/processor.h> #include <asm/math_emu.h> +#include <asm/tlbflush.h> #include <asm/uaccess.h> #include <asm/ptrace.h> #include <asm/i387.h> @@ -195,7 +196,7 @@ void fpu_init(void) if (cpu_has_xmm) cr4_mask |= X86_CR4_OSXMMEXCPT; if (cr4_mask) - set_in_cr4(cr4_mask); + cr4_set_bits(cr4_mask); cr0 = read_cr0(); cr0 &= ~(X86_CR0_TS|X86_CR0_EM); /* clear TS and EM */ diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index 6ad8a63..a388bb8 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -29,6 +29,7 @@ #include <asm/fpu-internal.h> #include <asm/debugreg.h> #include <asm/nmi.h> +#include <asm/tlbflush.h> /* * per-CPU TSS segments. Threads are completely 'soft' on Linux, @@ -142,7 +143,7 @@ void flush_thread(void) static void hard_disable_TSC(void) { - write_cr4(read_cr4() | X86_CR4_TSD); + cr4_set_bits(X86_CR4_TSD); } void disable_TSC(void) @@ -159,7 +160,7 @@ void disable_TSC(void) static void hard_enable_TSC(void) { - write_cr4(read_cr4() & ~X86_CR4_TSD); + cr4_clear_bits(X86_CR4_TSD); } static void enable_TSC(void) diff --git a/arch/x86/kernel/xsave.c b/arch/x86/kernel/xsave.c index 8be1e17..cdc6cf9 100644 --- a/arch/x86/kernel/xsave.c +++ b/arch/x86/kernel/xsave.c @@ -12,6 +12,7 @@ #include <asm/i387.h> #include <asm/fpu-internal.h> #include <asm/sigframe.h> +#include <asm/tlbflush.h> #include <asm/xcr.h> /* @@ -454,7 +455,7 @@ static void prepare_fx_sw_frame(void) */ static inline void xstate_enable(void) { - set_in_cr4(X86_CR4_OSXSAVE); + cr4_set_bits(X86_CR4_OSXSAVE); xsetbv(XCR_XFEATURE_ENABLED_MASK, pcntxt_mask); } diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 54bda28..0964bed 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -2771,7 +2771,7 @@ static int hardware_enable(void) /* enable and lock */ wrmsrl(MSR_IA32_FEATURE_CONTROL, old | test_bits); } - write_cr4(read_cr4() | X86_CR4_VMXE); /* FIXME: not cpu hotplug safe */ + cr4_set_bits(X86_CR4_VMXE); if (vmm_exclusive) { kvm_cpu_vmxon(phys_addr); @@ -2808,7 +2808,7 @@ static void hardware_disable(void) vmclear_local_loaded_vmcss(); kvm_cpu_vmxoff(); } - write_cr4(read_cr4() & ~X86_CR4_VMXE); + cr4_clear_bits(X86_CR4_VMXE); } static __init int adjust_vmx_controls(u32 ctl_min, u32 ctl_opt, diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index 66dba36..73b37cd 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -144,11 +144,11 @@ static void __init probe_page_size_mask(void) /* Enable PSE if available */ if (cpu_has_pse) - set_in_cr4(X86_CR4_PSE); + cr4_set_bits_and_update_boot(X86_CR4_PSE); /* Enable PGE if available */ if (cpu_has_pge) { - set_in_cr4(X86_CR4_PGE); + cr4_set_bits_and_update_boot(X86_CR4_PGE); __supported_pte_mask |= _PAGE_GLOBAL; } } diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index fac5e4f..7d67146 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -1483,10 +1483,10 @@ static void xen_pvh_set_cr_flags(int cpu) * set them here. For all, OSFXSR OSXMMEXCPT are set in fpu_init. */ if (cpu_has_pse) - set_in_cr4(X86_CR4_PSE); + cr4_set_bits_and_update_boot(X86_CR4_PSE); if (cpu_has_pge) - set_in_cr4(X86_CR4_PGE); + cr4_set_bits_and_update_boot(X86_CR4_PGE); } /* diff --git a/drivers/lguest/x86/core.c b/drivers/lguest/x86/core.c index 922a1ac..6adfd7b 100644 --- a/drivers/lguest/x86/core.c +++ b/drivers/lguest/x86/core.c @@ -47,6 +47,7 @@ #include <asm/lguest.h> #include <asm/uaccess.h> #include <asm/i387.h> +#include <asm/tlbflush.h> #include "../lg.h" static int cpu_had_pge; @@ -452,9 +453,9 @@ void lguest_arch_handle_trap(struct lg_cpu *cpu) static void adjust_pge(void *on) { if (on) - write_cr4(read_cr4() | X86_CR4_PGE); + cr4_set_bits(X86_CR4_PGE); else - write_cr4(read_cr4() & ~X86_CR4_PGE); + cr4_clear_bits(X86_CR4_PGE); } /*H:020 -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe stable" in