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author | Ingo Molnar <mingo@kernel.org> | 2018-02-26 08:45:20 +0100 |
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committer | Ingo Molnar <mingo@kernel.org> | 2018-02-26 08:48:08 +0100 |
commit | 1ea4fe84973854a7302e4d1c479f10ae25a93e4a (patch) | |
tree | 742fd3a20f74a451c2f377654a27a043579d0ca2 /arch/x86/boot | |
parent | ef61f8a340fd6d49df6b367785743febc47320c1 (diff) | |
parent | 4440977be1347d43503f381716e4918413b5a6f0 (diff) | |
download | linux-stable-1ea4fe84973854a7302e4d1c479f10ae25a93e4a.tar.gz linux-stable-1ea4fe84973854a7302e4d1c479f10ae25a93e4a.tar.bz2 linux-stable-1ea4fe84973854a7302e4d1c479f10ae25a93e4a.zip |
Merge branch 'x86/boot' into x86/mm, to unify branches
Both x86/mm and x86/boot contain 5-level paging related patches,
unify them to have a single tree to work against.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/boot')
-rw-r--r-- | arch/x86/boot/compressed/Makefile | 2 | ||||
-rw-r--r-- | arch/x86/boot/compressed/head_64.S | 41 | ||||
-rw-r--r-- | arch/x86/boot/compressed/kaslr_64.c (renamed from arch/x86/boot/compressed/pagetable.c) | 0 | ||||
-rw-r--r-- | arch/x86/boot/compressed/pgtable_64.c | 25 |
4 files changed, 32 insertions, 36 deletions
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index f25e1530e064..1f734cd98fd3 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -78,7 +78,7 @@ vmlinux-objs-y := $(obj)/vmlinux.lds $(obj)/head_$(BITS).o $(obj)/misc.o \ vmlinux-objs-$(CONFIG_EARLY_PRINTK) += $(obj)/early_serial_console.o vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr.o ifdef CONFIG_X86_64 - vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/pagetable.o + vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr_64.o vmlinux-objs-y += $(obj)/mem_encrypt.o vmlinux-objs-y += $(obj)/pgtable_64.o endif diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index fc313e29fe2c..d598d65db32c 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -304,20 +304,6 @@ ENTRY(startup_64) /* Set up the stack */ leaq boot_stack_end(%rbx), %rsp -#ifdef CONFIG_X86_5LEVEL - /* - * Check if we need to enable 5-level paging. - * RSI holds real mode data and need to be preserved across - * a function call. - */ - pushq %rsi - call l5_paging_required - popq %rsi - - /* If l5_paging_required() returned zero, we're done here. */ - cmpq $0, %rax - je lvl5 - /* * At this point we are in long mode with 4-level paging enabled, * but we want to enable 5-level paging. @@ -325,12 +311,28 @@ ENTRY(startup_64) * The problem is that we cannot do it directly. Setting LA57 in * long mode would trigger #GP. So we need to switch off long mode * first. + */ + + /* + * paging_prepare() sets up the trampoline and checks if we need to + * enable 5-level paging. * - * NOTE: This is not going to work if bootloader put us above 4G - * limit. + * Address of the trampoline is returned in RAX. + * Non zero RDX on return means we need to enable 5-level paging. * - * The first step is go into compatibility mode. + * RSI holds real mode data and needs to be preserved across + * this function call. */ + pushq %rsi + call paging_prepare + popq %rsi + + /* Save the trampoline address in RCX */ + movq %rax, %rcx + + /* Check if we need to enable 5-level paging */ + cmpq $0, %rdx + jz lvl5 /* Clear additional page table */ leaq lvl5_pgtable(%rbx), %rdi @@ -352,7 +354,6 @@ ENTRY(startup_64) pushq %rax lretq lvl5: -#endif /* Zero EFLAGS */ pushq $0 @@ -490,7 +491,6 @@ relocated: jmp *%rax .code32 -#ifdef CONFIG_X86_5LEVEL compatible_mode: /* Setup data and stack segments */ movl $__KERNEL_DS, %eax @@ -526,7 +526,6 @@ compatible_mode: movl %eax, %cr0 lret -#endif no_longmode: /* This isn't an x86-64 CPU so hang */ @@ -585,7 +584,5 @@ boot_stack_end: .balign 4096 pgtable: .fill BOOT_PGT_SIZE, 1, 0 -#ifdef CONFIG_X86_5LEVEL lvl5_pgtable: .fill PAGE_SIZE, 1, 0 -#endif diff --git a/arch/x86/boot/compressed/pagetable.c b/arch/x86/boot/compressed/kaslr_64.c index b5e5e02f8cde..b5e5e02f8cde 100644 --- a/arch/x86/boot/compressed/pagetable.c +++ b/arch/x86/boot/compressed/kaslr_64.c diff --git a/arch/x86/boot/compressed/pgtable_64.c b/arch/x86/boot/compressed/pgtable_64.c index b4469a37e9a1..3f1697fcc7a8 100644 --- a/arch/x86/boot/compressed/pgtable_64.c +++ b/arch/x86/boot/compressed/pgtable_64.c @@ -9,20 +9,19 @@ */ unsigned long __force_order; -int l5_paging_required(void) -{ - /* Check if leaf 7 is supported. */ - - if (native_cpuid_eax(0) < 7) - return 0; +struct paging_config { + unsigned long trampoline_start; + unsigned long l5_required; +}; - /* Check if la57 is supported. */ - if (!(native_cpuid_ecx(7) & (1 << (X86_FEATURE_LA57 & 31)))) - return 0; +struct paging_config paging_prepare(void) +{ + struct paging_config paging_config = {}; - /* Check if 5-level paging has already been enabled. */ - if (native_read_cr4() & X86_CR4_LA57) - return 0; + /* Check if LA57 is desired and supported */ + if (IS_ENABLED(CONFIG_X86_5LEVEL) && native_cpuid_eax(0) >= 7 && + (native_cpuid_ecx(7) & (1 << (X86_FEATURE_LA57 & 31)))) + paging_config.l5_required = 1; - return 1; + return paging_config; } |