diff options
Diffstat (limited to 'common/recipes-kernel/linux/linux-yocto-4.9.21/0030-kaiser-use-ALTERNATIVE-instead-of-x86_cr3_pcid_noflu.patch')
| -rw-r--r-- | common/recipes-kernel/linux/linux-yocto-4.9.21/0030-kaiser-use-ALTERNATIVE-instead-of-x86_cr3_pcid_noflu.patch | 137 |
1 files changed, 0 insertions, 137 deletions
diff --git a/common/recipes-kernel/linux/linux-yocto-4.9.21/0030-kaiser-use-ALTERNATIVE-instead-of-x86_cr3_pcid_noflu.patch b/common/recipes-kernel/linux/linux-yocto-4.9.21/0030-kaiser-use-ALTERNATIVE-instead-of-x86_cr3_pcid_noflu.patch deleted file mode 100644 index f0bb8bea..00000000 --- a/common/recipes-kernel/linux/linux-yocto-4.9.21/0030-kaiser-use-ALTERNATIVE-instead-of-x86_cr3_pcid_noflu.patch +++ /dev/null @@ -1,137 +0,0 @@ -From 1aa1f0422243ae2e5e8b07d7e2c4004544d39727 Mon Sep 17 00:00:00 2001 -From: Hugh Dickins <hughd@google.com> -Date: Tue, 3 Oct 2017 20:49:04 -0700 -Subject: [PATCH 030/103] kaiser: use ALTERNATIVE instead of - x86_cr3_pcid_noflush - -Now that we're playing the ALTERNATIVE game, use that more efficient -method: instead of user-mapping an extra page, and reading an extra -cacheline each time for x86_cr3_pcid_noflush. - -Neel has found that __stringify(bts $X86_CR3_PCID_NOFLUSH_BIT, %rax) -is a working substitute for the "bts $63, %rax" in these ALTERNATIVEs; -but the one line with $63 in looks clearer, so let's stick with that. - -Worried about what happens with an ALTERNATIVE between the jump and -jump label in another ALTERNATIVE? I was, but have checked the -combinations in SWITCH_KERNEL_CR3_NO_STACK at entry_SYSCALL_64, -and it does a good job. - -Signed-off-by: Hugh Dickins <hughd@google.com> -Acked-by: Jiri Kosina <jkosina@suse.cz> -Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> ---- - arch/x86/entry/entry_64.S | 7 ++++--- - arch/x86/include/asm/kaiser.h | 6 +++--- - arch/x86/mm/kaiser.c | 11 +---------- - 3 files changed, 8 insertions(+), 16 deletions(-) - -diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S -index bbb38ac..d4ba81e 100644 ---- a/arch/x86/entry/entry_64.S -+++ b/arch/x86/entry/entry_64.S -@@ -1084,7 +1084,8 @@ ENTRY(paranoid_entry) - jz 2f - orl $2, %ebx - andq $(~(X86_CR3_PCID_ASID_MASK | KAISER_SHADOW_PGD_OFFSET)), %rax -- orq x86_cr3_pcid_noflush, %rax -+ /* If PCID enabled, set X86_CR3_PCID_NOFLUSH_BIT */ -+ ALTERNATIVE "", "bts $63, %rax", X86_FEATURE_PCID - movq %rax, %cr3 - 2: - #endif -@@ -1342,7 +1343,7 @@ ENTRY(nmi) - /* %rax is saved above, so OK to clobber here */ - ALTERNATIVE "jmp 2f", "movq %cr3, %rax", X86_FEATURE_KAISER - /* If PCID enabled, NOFLUSH now and NOFLUSH on return */ -- orq x86_cr3_pcid_noflush, %rax -+ ALTERNATIVE "", "bts $63, %rax", X86_FEATURE_PCID - pushq %rax - /* mask off "user" bit of pgd address and 12 PCID bits: */ - andq $(~(X86_CR3_PCID_ASID_MASK | KAISER_SHADOW_PGD_OFFSET)), %rax -@@ -1586,7 +1587,7 @@ end_repeat_nmi: - /* %rax is saved above, so OK to clobber here */ - ALTERNATIVE "jmp 2f", "movq %cr3, %rax", X86_FEATURE_KAISER - /* If PCID enabled, NOFLUSH now and NOFLUSH on return */ -- orq x86_cr3_pcid_noflush, %rax -+ ALTERNATIVE "", "bts $63, %rax", X86_FEATURE_PCID - pushq %rax - /* mask off "user" bit of pgd address and 12 PCID bits: */ - andq $(~(X86_CR3_PCID_ASID_MASK | KAISER_SHADOW_PGD_OFFSET)), %rax -diff --git a/arch/x86/include/asm/kaiser.h b/arch/x86/include/asm/kaiser.h -index 96643a9..906150d 100644 ---- a/arch/x86/include/asm/kaiser.h -+++ b/arch/x86/include/asm/kaiser.h -@@ -25,7 +25,8 @@ - .macro _SWITCH_TO_KERNEL_CR3 reg - movq %cr3, \reg - andq $(~(X86_CR3_PCID_ASID_MASK | KAISER_SHADOW_PGD_OFFSET)), \reg --orq x86_cr3_pcid_noflush, \reg -+/* If PCID enabled, set X86_CR3_PCID_NOFLUSH_BIT */ -+ALTERNATIVE "", "bts $63, \reg", X86_FEATURE_PCID - movq \reg, %cr3 - .endm - -@@ -39,7 +40,7 @@ movq \reg, %cr3 - movq %cr3, \reg - orq PER_CPU_VAR(x86_cr3_pcid_user), \reg - js 9f --/* FLUSH this time, reset to NOFLUSH for next time (if PCID enabled) */ -+/* If PCID enabled, FLUSH this time, reset to NOFLUSH for next time */ - movb \regb, PER_CPU_VAR(x86_cr3_pcid_user+7) - 9: - movq \reg, %cr3 -@@ -90,7 +91,6 @@ movq PER_CPU_VAR(unsafe_stack_register_backup), %rax - */ - DECLARE_PER_CPU_USER_MAPPED(unsigned long, unsafe_stack_register_backup); - --extern unsigned long x86_cr3_pcid_noflush; - DECLARE_PER_CPU(unsigned long, x86_cr3_pcid_user); - - extern char __per_cpu_user_mapped_start[], __per_cpu_user_mapped_end[]; -diff --git a/arch/x86/mm/kaiser.c b/arch/x86/mm/kaiser.c -index 1840aa0..b8aa9ad 100644 ---- a/arch/x86/mm/kaiser.c -+++ b/arch/x86/mm/kaiser.c -@@ -31,7 +31,6 @@ DEFINE_PER_CPU_USER_MAPPED(unsigned long, unsafe_stack_register_backup); - * This is also handy because systems that do not support PCIDs - * just end up or'ing a 0 into their CR3, which does no harm. - */ --unsigned long x86_cr3_pcid_noflush __read_mostly; - DEFINE_PER_CPU(unsigned long, x86_cr3_pcid_user); - - /* -@@ -356,10 +355,6 @@ void __init kaiser_init(void) - kaiser_add_user_map_early(&debug_idt_table, - sizeof(gate_desc) * NR_VECTORS, - __PAGE_KERNEL); -- -- kaiser_add_user_map_early(&x86_cr3_pcid_noflush, -- sizeof(x86_cr3_pcid_noflush), -- __PAGE_KERNEL); - } - - /* Add a mapping to the shadow mapping, and synchronize the mappings */ -@@ -433,18 +428,14 @@ pgd_t kaiser_set_shadow_pgd(pgd_t *pgdp, pgd_t pgd) - - void kaiser_setup_pcid(void) - { -- unsigned long kern_cr3 = 0; - unsigned long user_cr3 = KAISER_SHADOW_PGD_OFFSET; - -- if (this_cpu_has(X86_FEATURE_PCID)) { -- kern_cr3 |= X86_CR3_PCID_KERN_NOFLUSH; -+ if (this_cpu_has(X86_FEATURE_PCID)) - user_cr3 |= X86_CR3_PCID_USER_NOFLUSH; -- } - /* - * These variables are used by the entry/exit - * code to change PCID and pgd and TLB flushing. - */ -- x86_cr3_pcid_noflush = kern_cr3; - this_cpu_write(x86_cr3_pcid_user, user_cr3); - } - --- -2.7.4 - |