diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-08-26 10:13:21 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-08-26 10:13:21 -0700 |
commit | 2a8a2b7c49d6eb5f3348892c4676267376cfd40b (patch) | |
tree | 2342006a8a8fa0d02b147c4d4482146a9f6353f6 /arch/x86 | |
parent | de3750351c0de35472299506ace61a01f2bfc567 (diff) | |
parent | 6a012288d6906fee1dbc244050ade1dafe4a9c8d (diff) | |
download | linux-2a8a2b7c49d6eb5f3348892c4676267376cfd40b.tar.bz2 |
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
- Correct the L1TF fallout on 32bit and the off by one in the 'too much
RAM for protection' calculation.
- Add a helpful kernel message for the 'too much RAM' case
- Unbreak the VDSO in case that the compiler desides to use indirect
jumps/calls and emits retpolines which cannot be resolved because the
kernel uses its own thunks, which does not work for the VDSO. Make it
use the builtin thunks.
- Re-export start_thread() which was unexported when the 32/64bit
implementation was unified. start_thread() is required by modular
binfmt handlers.
- Trivial cleanups
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/speculation/l1tf: Suggest what to do on systems with too much RAM
x86/speculation/l1tf: Fix off-by-one error when warning that system has too much RAM
x86/kvm/vmx: Remove duplicate l1d flush definitions
x86/speculation/l1tf: Fix overflow in l1tf_pfn_limit() on 32bit
x86/process: Re-export start_thread()
x86/mce: Add notifier_block forward declaration
x86/vdso: Fix vDSO build if a retpoline is emitted
Diffstat (limited to 'arch/x86')
-rw-r--r-- | arch/x86/entry/vdso/Makefile | 6 | ||||
-rw-r--r-- | arch/x86/include/asm/mce.h | 1 | ||||
-rw-r--r-- | arch/x86/include/asm/processor.h | 4 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/bugs.c | 4 | ||||
-rw-r--r-- | arch/x86/kernel/process_64.c | 1 | ||||
-rw-r--r-- | arch/x86/kvm/vmx.c | 3 | ||||
-rw-r--r-- | arch/x86/mm/init.c | 4 | ||||
-rw-r--r-- | arch/x86/mm/mmap.c | 2 |
8 files changed, 15 insertions, 10 deletions
diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile index 9f695f517747..fa3f439f0a92 100644 --- a/arch/x86/entry/vdso/Makefile +++ b/arch/x86/entry/vdso/Makefile @@ -68,9 +68,9 @@ $(obj)/vdso-image-%.c: $(obj)/vdso%.so.dbg $(obj)/vdso%.so $(obj)/vdso2c FORCE CFL := $(PROFILING) -mcmodel=small -fPIC -O2 -fasynchronous-unwind-tables -m64 \ $(filter -g%,$(KBUILD_CFLAGS)) $(call cc-option, -fno-stack-protector) \ -fno-omit-frame-pointer -foptimize-sibling-calls \ - -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO + -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO $(RETPOLINE_VDSO_CFLAGS) -$(vobjs): KBUILD_CFLAGS := $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS)) $(CFL) +$(vobjs): KBUILD_CFLAGS := $(filter-out $(GCC_PLUGINS_CFLAGS) $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS)) $(CFL) # # vDSO code runs in userspace and -pg doesn't help with profiling anyway. @@ -132,11 +132,13 @@ KBUILD_CFLAGS_32 := $(filter-out -mcmodel=kernel,$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 := $(filter-out -fno-pic,$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 := $(filter-out -mfentry,$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 := $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS_32)) +KBUILD_CFLAGS_32 := $(filter-out $(RETPOLINE_CFLAGS),$(KBUILD_CFLAGS_32)) KBUILD_CFLAGS_32 += -m32 -msoft-float -mregparm=0 -fpic KBUILD_CFLAGS_32 += $(call cc-option, -fno-stack-protector) KBUILD_CFLAGS_32 += $(call cc-option, -foptimize-sibling-calls) KBUILD_CFLAGS_32 += -fno-omit-frame-pointer KBUILD_CFLAGS_32 += -DDISABLE_BRANCH_PROFILING +KBUILD_CFLAGS_32 += $(RETPOLINE_VDSO_CFLAGS) $(obj)/vdso32.so.dbg: KBUILD_CFLAGS = $(KBUILD_CFLAGS_32) $(obj)/vdso32.so.dbg: FORCE \ diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h index 8c7b3e5a2d01..3a17107594c8 100644 --- a/arch/x86/include/asm/mce.h +++ b/arch/x86/include/asm/mce.h @@ -148,6 +148,7 @@ enum mce_notifier_prios { MCE_PRIO_LOWEST = 0, }; +struct notifier_block; extern void mce_register_decode_chain(struct notifier_block *nb); extern void mce_unregister_decode_chain(struct notifier_block *nb); diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 682286aca881..c24297268ebc 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -181,9 +181,9 @@ extern const struct seq_operations cpuinfo_op; extern void cpu_detect(struct cpuinfo_x86 *c); -static inline unsigned long l1tf_pfn_limit(void) +static inline unsigned long long l1tf_pfn_limit(void) { - return BIT(boot_cpu_data.x86_phys_bits - 1 - PAGE_SHIFT) - 1; + return BIT_ULL(boot_cpu_data.x86_phys_bits - 1 - PAGE_SHIFT); } extern void early_cpu_init(void); diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index cb4a16292aa7..4c2313d0b9ca 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -702,6 +702,10 @@ static void __init l1tf_select_mitigation(void) half_pa = (u64)l1tf_pfn_limit() << PAGE_SHIFT; if (e820__mapped_any(half_pa, ULLONG_MAX - half_pa, E820_TYPE_RAM)) { pr_warn("System has more than MAX_PA/2 memory. L1TF mitigation not effective.\n"); + pr_info("You may make it effective by booting the kernel with mem=%llu parameter.\n", + half_pa); + pr_info("However, doing so will make a part of your RAM unusable.\n"); + pr_info("Reading https://www.kernel.org/doc/html/latest/admin-guide/l1tf.html might help you decide.\n"); return; } diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 476e3ddf8890..a451bc374b9b 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -384,6 +384,7 @@ start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp) start_thread_common(regs, new_ip, new_sp, __USER_CS, __USER_DS, 0); } +EXPORT_SYMBOL_GPL(start_thread); #ifdef CONFIG_COMPAT void compat_start_thread(struct pt_regs *regs, u32 new_ip, u32 new_sp) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 8dae47e7267a..1d26f3c4985b 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -10131,9 +10131,6 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu) * information but as all relevant affected CPUs have 32KiB L1D cache size * there is no point in doing so. */ -#define L1D_CACHE_ORDER 4 -static void *vmx_l1d_flush_pages; - static void vmx_l1d_flush(struct kvm_vcpu *vcpu) { int size = PAGE_SIZE << L1D_CACHE_ORDER; diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index 5c32a7665492..7a8fc26c1115 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -930,7 +930,7 @@ unsigned long max_swapfile_size(void) if (boot_cpu_has_bug(X86_BUG_L1TF)) { /* Limit the swap file size to MAX_PA/2 for L1TF workaround */ - unsigned long l1tf_limit = l1tf_pfn_limit() + 1; + unsigned long long l1tf_limit = l1tf_pfn_limit(); /* * We encode swap offsets also with 3 bits below those for pfn * which makes the usable limit higher. @@ -938,7 +938,7 @@ unsigned long max_swapfile_size(void) #if CONFIG_PGTABLE_LEVELS > 2 l1tf_limit <<= PAGE_SHIFT - SWP_OFFSET_FIRST_BIT; #endif - pages = min_t(unsigned long, l1tf_limit, pages); + pages = min_t(unsigned long long, l1tf_limit, pages); } return pages; } diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c index f40ab8185d94..1e95d57760cf 100644 --- a/arch/x86/mm/mmap.c +++ b/arch/x86/mm/mmap.c @@ -257,7 +257,7 @@ bool pfn_modify_allowed(unsigned long pfn, pgprot_t prot) /* If it's real memory always allow */ if (pfn_valid(pfn)) return true; - if (pfn > l1tf_pfn_limit() && !capable(CAP_SYS_ADMIN)) + if (pfn >= l1tf_pfn_limit() && !capable(CAP_SYS_ADMIN)) return false; return true; } |