From fc8d782677f163dee76427fdd8a92bebd2b50b23 Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Fri, 16 Nov 2012 13:57:13 -0800 Subject: x86: Use __pa_symbol instead of __pa on C visible symbols When I made an attempt at separating __pa_symbol and __pa I found that there were a number of cases where __pa was used on an obvious symbol. I also caught one non-obvious case as _brk_start and _brk_end are based on the address of __brk_base which is a C visible symbol. In mark_rodata_ro I was able to reduce the overhead of kernel symbol to virtual memory translation by using a combination of __va(__pa_symbol()) instead of page_address(virt_to_page()). Signed-off-by: Alexander Duyck Link: http://lkml.kernel.org/r/20121116215640.8521.80483.stgit@ahduyck-cp1.jf.intel.com Signed-off-by: H. Peter Anvin --- arch/x86/realmode/init.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'arch/x86/realmode/init.c') diff --git a/arch/x86/realmode/init.c b/arch/x86/realmode/init.c index cbca565af5bd..80450261215c 100644 --- a/arch/x86/realmode/init.c +++ b/arch/x86/realmode/init.c @@ -62,9 +62,9 @@ void __init setup_real_mode(void) __va(real_mode_header->trampoline_header); #ifdef CONFIG_X86_32 - trampoline_header->start = __pa(startup_32_smp); + trampoline_header->start = __pa_symbol(startup_32_smp); trampoline_header->gdt_limit = __BOOT_DS + 7; - trampoline_header->gdt_base = __pa(boot_gdt); + trampoline_header->gdt_base = __pa_symbol(boot_gdt); #else /* * Some AMD processors will #GP(0) if EFER.LMA is set in WRMSR @@ -78,8 +78,8 @@ void __init setup_real_mode(void) *trampoline_cr4_features = read_cr4(); trampoline_pgd = (u64 *) __va(real_mode_header->trampoline_pgd); - trampoline_pgd[0] = __pa(level3_ident_pgt) + _KERNPG_TABLE; - trampoline_pgd[511] = __pa(level3_kernel_pgt) + _KERNPG_TABLE; + trampoline_pgd[0] = __pa_symbol(level3_ident_pgt) + _KERNPG_TABLE; + trampoline_pgd[511] = __pa_symbol(level3_kernel_pgt) + _KERNPG_TABLE; #endif } -- cgit v1.2.3 From 231b3642a3c73fb9f1221dcb96fe8c0fbb658dfd Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Thu, 24 Jan 2013 12:19:47 -0800 Subject: x86, realmode: Set real_mode permissions early Trampoline code is executed by APs with kernel low mapping on 64bit. We need to set trampoline code to EXEC early before we boot APs. Found the problem after switching to #PF handler set page table, and we do not set initial kernel low mapping with EXEC anymore in arch/x86/kernel/head_64.S. Change to use early_initcall instead that will make sure trampoline will have EXEC set. -v2: Merge two comments according to Borislav Petkov Signed-off-by: Yinghai Lu Link: http://lkml.kernel.org/r/1359058816-7615-7-git-send-email-yinghai@kernel.org Signed-off-by: H. Peter Anvin --- arch/x86/realmode/init.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'arch/x86/realmode/init.c') diff --git a/arch/x86/realmode/init.c b/arch/x86/realmode/init.c index cbca565af5bd..c44ea7cf5741 100644 --- a/arch/x86/realmode/init.c +++ b/arch/x86/realmode/init.c @@ -84,10 +84,12 @@ void __init setup_real_mode(void) } /* - * set_real_mode_permissions() gets called very early, to guarantee the - * availability of low memory. This is before the proper kernel page + * setup_real_mode() gets called very early, to guarantee the + * availability of low memory. This is before the proper kernel page * tables are set up, so we cannot set page permissions in that - * function. Thus, we use an arch_initcall instead. + * function. Also trampoline code will be executed by APs so we + * need to mark it executable at do_pre_smp_initcalls() at least, + * thus run it as a early_initcall(). */ static int __init set_real_mode_permissions(void) { @@ -111,5 +113,4 @@ static int __init set_real_mode_permissions(void) return 0; } - -arch_initcall(set_real_mode_permissions); +early_initcall(set_real_mode_permissions); -- cgit v1.2.3 From 9735e91e9c29c0d8fe432aef1152e43e50bdb316 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Thu, 24 Jan 2013 12:19:50 -0800 Subject: x86, 64bit, realmode: Use init_level4_pgt to set trampoline_pgd directly with #PF handler way to set early page table, level3_ident will go away with 64bit native path. So just use entries in init_level4_pgt to set them in trampoline_pgd. Signed-off-by: Yinghai Lu Link: http://lkml.kernel.org/r/1359058816-7615-10-git-send-email-yinghai@kernel.org Cc: Jarkko Sakkinen Acked-by: Jarkko Sakkinen Signed-off-by: H. Peter Anvin --- arch/x86/realmode/init.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/x86/realmode/init.c') diff --git a/arch/x86/realmode/init.c b/arch/x86/realmode/init.c index c44ea7cf5741..ffee06ac7de9 100644 --- a/arch/x86/realmode/init.c +++ b/arch/x86/realmode/init.c @@ -78,8 +78,8 @@ void __init setup_real_mode(void) *trampoline_cr4_features = read_cr4(); trampoline_pgd = (u64 *) __va(real_mode_header->trampoline_pgd); - trampoline_pgd[0] = __pa(level3_ident_pgt) + _KERNPG_TABLE; - trampoline_pgd[511] = __pa(level3_kernel_pgt) + _KERNPG_TABLE; + trampoline_pgd[0] = init_level4_pgt[pgd_index(__PAGE_OFFSET)].pgd; + trampoline_pgd[511] = init_level4_pgt[511].pgd; #endif } -- cgit v1.2.3 From 4f7b92263ad68cdc72b11808320d9c881bfa857e Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Thu, 24 Jan 2013 12:19:51 -0800 Subject: x86, realmode: Separate real_mode reserve and setup After we switch to use #PF handler help to set page table, init_level4_pgt will only have entries set after init_mem_mapping(). We need to move copying init_level4_pgt to trampoline_pgd after that. So split reserve and setup, and move the setup after init_mem_mapping() Signed-off-by: Yinghai Lu Link: http://lkml.kernel.org/r/1359058816-7615-11-git-send-email-yinghai@kernel.org Cc: Jarkko Sakkinen Acked-by: Jarkko Sakkinen Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/realmode.h | 3 ++- arch/x86/kernel/setup.c | 4 +++- arch/x86/realmode/init.c | 32 ++++++++++++++++++++------------ 3 files changed, 25 insertions(+), 14 deletions(-) (limited to 'arch/x86/realmode/init.c') diff --git a/arch/x86/include/asm/realmode.h b/arch/x86/include/asm/realmode.h index fe1ec5bcd846..9c6b890d5e7a 100644 --- a/arch/x86/include/asm/realmode.h +++ b/arch/x86/include/asm/realmode.h @@ -58,6 +58,7 @@ extern unsigned char boot_gdt[]; extern unsigned char secondary_startup_64[]; #endif -extern void __init setup_real_mode(void); +void reserve_real_mode(void); +void setup_real_mode(void); #endif /* _ARCH_X86_REALMODE_H */ diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 5552d04b0cc1..85a8290801df 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -999,12 +999,14 @@ void __init setup_arch(char **cmdline_p) printk(KERN_DEBUG "initial memory mapped: [mem 0x00000000-%#010lx]\n", (max_pfn_mapped<