diff options
Diffstat (limited to 'arch')
-rw-r--r-- | arch/x86/entry/syscall_32.c | 10 | ||||
-rw-r--r-- | arch/x86/entry/syscall_64.c | 9 | ||||
-rw-r--r-- | arch/x86/entry/syscall_x32.c | 7 | ||||
-rw-r--r-- | arch/x86/entry/syscalls/syscall_32.tbl | 6 | ||||
-rw-r--r-- | arch/x86/entry/syscalls/syscall_64.tbl | 6 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/bugs.c | 16 | ||||
-rw-r--r-- | arch/x86/um/sys_call_table_32.c | 10 | ||||
-rw-r--r-- | arch/x86/um/sys_call_table_64.c | 11 |
8 files changed, 47 insertions, 28 deletions
diff --git a/arch/x86/entry/syscall_32.c b/arch/x86/entry/syscall_32.c index c2235bae17ef..8cc9950d7104 100644 --- a/arch/x86/entry/syscall_32.c +++ b/arch/x86/entry/syscall_32.c @@ -14,9 +14,12 @@ #endif #define __SYSCALL(nr, sym) extern long __ia32_##sym(const struct pt_regs *); - +#define __SYSCALL_NORETURN(nr, sym) extern long __noreturn __ia32_##sym(const struct pt_regs *); #include <asm/syscalls_32.h> -#undef __SYSCALL +#undef __SYSCALL + +#undef __SYSCALL_NORETURN +#define __SYSCALL_NORETURN __SYSCALL /* * The sys_call_table[] is no longer used for system calls, but @@ -28,11 +31,10 @@ const sys_call_ptr_t sys_call_table[] = { #include <asm/syscalls_32.h> }; -#undef __SYSCALL +#undef __SYSCALL #endif #define __SYSCALL(nr, sym) case nr: return __ia32_##sym(regs); - long ia32_sys_call(const struct pt_regs *regs, unsigned int nr) { switch (nr) { diff --git a/arch/x86/entry/syscall_64.c b/arch/x86/entry/syscall_64.c index 33b3f09e6f15..ba8354424860 100644 --- a/arch/x86/entry/syscall_64.c +++ b/arch/x86/entry/syscall_64.c @@ -8,8 +8,12 @@ #include <asm/syscall.h> #define __SYSCALL(nr, sym) extern long __x64_##sym(const struct pt_regs *); +#define __SYSCALL_NORETURN(nr, sym) extern long __noreturn __x64_##sym(const struct pt_regs *); #include <asm/syscalls_64.h> -#undef __SYSCALL +#undef __SYSCALL + +#undef __SYSCALL_NORETURN +#define __SYSCALL_NORETURN __SYSCALL /* * The sys_call_table[] is no longer used for system calls, but @@ -20,10 +24,9 @@ const sys_call_ptr_t sys_call_table[] = { #include <asm/syscalls_64.h> }; -#undef __SYSCALL +#undef __SYSCALL #define __SYSCALL(nr, sym) case nr: return __x64_##sym(regs); - long x64_sys_call(const struct pt_regs *regs, unsigned int nr) { switch (nr) { diff --git a/arch/x86/entry/syscall_x32.c b/arch/x86/entry/syscall_x32.c index 03de4a932131..fb77908f44f3 100644 --- a/arch/x86/entry/syscall_x32.c +++ b/arch/x86/entry/syscall_x32.c @@ -8,11 +8,14 @@ #include <asm/syscall.h> #define __SYSCALL(nr, sym) extern long __x64_##sym(const struct pt_regs *); +#define __SYSCALL_NORETURN(nr, sym) extern long __noreturn __x64_##sym(const struct pt_regs *); #include <asm/syscalls_x32.h> -#undef __SYSCALL +#undef __SYSCALL -#define __SYSCALL(nr, sym) case nr: return __x64_##sym(regs); +#undef __SYSCALL_NORETURN +#define __SYSCALL_NORETURN __SYSCALL +#define __SYSCALL(nr, sym) case nr: return __x64_##sym(regs); long x32_sys_call(const struct pt_regs *regs, unsigned int nr) { switch (nr) { diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl index ecf5f146783f..534c74b14fab 100644 --- a/arch/x86/entry/syscalls/syscall_32.tbl +++ b/arch/x86/entry/syscalls/syscall_32.tbl @@ -3,7 +3,7 @@ # 32-bit system call numbers and entry vectors # # The format is: -# <number> <abi> <name> <entry point> <compat entry point> +# <number> <abi> <name> <entry point> [<compat entry point> [noreturn]] # # The __ia32_sys and __ia32_compat_sys stubs are created on-the-fly for # sys_*() system calls and compat_sys_*() compat system calls if @@ -13,7 +13,7 @@ # The abi is always "i386" for this file. # 0 i386 restart_syscall sys_restart_syscall -1 i386 exit sys_exit +1 i386 exit sys_exit - noreturn 2 i386 fork sys_fork 3 i386 read sys_read 4 i386 write sys_write @@ -264,7 +264,7 @@ 249 i386 io_cancel sys_io_cancel 250 i386 fadvise64 sys_ia32_fadvise64 # 251 is available for reuse (was briefly sys_set_zone_reclaim) -252 i386 exit_group sys_exit_group +252 i386 exit_group sys_exit_group - noreturn 253 i386 lookup_dcookie 254 i386 epoll_create sys_epoll_create 255 i386 epoll_ctl sys_epoll_ctl diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl index 129bdd475cf0..097e5a18db52 100644 --- a/arch/x86/entry/syscalls/syscall_64.tbl +++ b/arch/x86/entry/syscalls/syscall_64.tbl @@ -3,7 +3,7 @@ # 64-bit system call numbers and entry vectors # # The format is: -# <number> <abi> <name> <entry point> +# <number> <abi> <name> <entry point> [<compat entry point> [noreturn]] # # The __x64_sys_*() stubs are created on-the-fly for sys_*() system calls # @@ -69,7 +69,7 @@ 57 common fork sys_fork 58 common vfork sys_vfork 59 64 execve sys_execve -60 common exit sys_exit +60 common exit sys_exit - noreturn 61 common wait4 sys_wait4 62 common kill sys_kill 63 common uname sys_newuname @@ -240,7 +240,7 @@ 228 common clock_gettime sys_clock_gettime 229 common clock_getres sys_clock_getres 230 common clock_nanosleep sys_clock_nanosleep -231 common exit_group sys_exit_group +231 common exit_group sys_exit_group - noreturn 232 common epoll_wait sys_epoll_wait 233 common epoll_ctl sys_epoll_ctl 234 common tgkill sys_tgkill diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index b6f927f6c567..45675da354f3 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -1625,6 +1625,7 @@ static bool __init spec_ctrl_bhi_dis(void) enum bhi_mitigations { BHI_MITIGATION_OFF, BHI_MITIGATION_ON, + BHI_MITIGATION_VMEXIT_ONLY, }; static enum bhi_mitigations bhi_mitigation __ro_after_init = @@ -1639,6 +1640,8 @@ static int __init spectre_bhi_parse_cmdline(char *str) bhi_mitigation = BHI_MITIGATION_OFF; else if (!strcmp(str, "on")) bhi_mitigation = BHI_MITIGATION_ON; + else if (!strcmp(str, "vmexit")) + bhi_mitigation = BHI_MITIGATION_VMEXIT_ONLY; else pr_err("Ignoring unknown spectre_bhi option (%s)", str); @@ -1659,19 +1662,22 @@ static void __init bhi_select_mitigation(void) return; } + /* Mitigate in hardware if supported */ if (spec_ctrl_bhi_dis()) return; if (!IS_ENABLED(CONFIG_X86_64)) return; - /* Mitigate KVM by default */ - setup_force_cpu_cap(X86_FEATURE_CLEAR_BHB_LOOP_ON_VMEXIT); - pr_info("Spectre BHI mitigation: SW BHB clearing on vm exit\n"); + if (bhi_mitigation == BHI_MITIGATION_VMEXIT_ONLY) { + pr_info("Spectre BHI mitigation: SW BHB clearing on VM exit only\n"); + setup_force_cpu_cap(X86_FEATURE_CLEAR_BHB_LOOP_ON_VMEXIT); + return; + } - /* Mitigate syscalls when the mitigation is forced =on */ + pr_info("Spectre BHI mitigation: SW BHB clearing on syscall and VM exit\n"); setup_force_cpu_cap(X86_FEATURE_CLEAR_BHB_LOOP); - pr_info("Spectre BHI mitigation: SW BHB clearing on syscall\n"); + setup_force_cpu_cap(X86_FEATURE_CLEAR_BHB_LOOP_ON_VMEXIT); } static void __init spectre_v2_select_mitigation(void) diff --git a/arch/x86/um/sys_call_table_32.c b/arch/x86/um/sys_call_table_32.c index 89df5d89d664..51655133eee3 100644 --- a/arch/x86/um/sys_call_table_32.c +++ b/arch/x86/um/sys_call_table_32.c @@ -9,6 +9,10 @@ #include <linux/cache.h> #include <asm/syscall.h> +extern asmlinkage long sys_ni_syscall(unsigned long, unsigned long, + unsigned long, unsigned long, + unsigned long, unsigned long); + /* * Below you can see, in terms of #define's, the differences between the x86-64 * and the UML syscall table. @@ -22,15 +26,13 @@ #define sys_vm86 sys_ni_syscall #define __SYSCALL_WITH_COMPAT(nr, native, compat) __SYSCALL(nr, native) +#define __SYSCALL_NORETURN __SYSCALL #define __SYSCALL(nr, sym) extern asmlinkage long sym(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long); #include <asm/syscalls_32.h> +#undef __SYSCALL -#undef __SYSCALL #define __SYSCALL(nr, sym) sym, - -extern asmlinkage long sys_ni_syscall(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long); - const sys_call_ptr_t sys_call_table[] ____cacheline_aligned = { #include <asm/syscalls_32.h> }; diff --git a/arch/x86/um/sys_call_table_64.c b/arch/x86/um/sys_call_table_64.c index b0b4cfd2308c..943d414f2109 100644 --- a/arch/x86/um/sys_call_table_64.c +++ b/arch/x86/um/sys_call_table_64.c @@ -9,6 +9,10 @@ #include <linux/cache.h> #include <asm/syscall.h> +extern asmlinkage long sys_ni_syscall(unsigned long, unsigned long, + unsigned long, unsigned long, + unsigned long, unsigned long); + /* * Below you can see, in terms of #define's, the differences between the x86-64 * and the UML syscall table. @@ -18,14 +22,13 @@ #define sys_iopl sys_ni_syscall #define sys_ioperm sys_ni_syscall +#define __SYSCALL_NORETURN __SYSCALL + #define __SYSCALL(nr, sym) extern asmlinkage long sym(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long); #include <asm/syscalls_64.h> +#undef __SYSCALL -#undef __SYSCALL #define __SYSCALL(nr, sym) sym, - -extern asmlinkage long sys_ni_syscall(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long); - const sys_call_ptr_t sys_call_table[] ____cacheline_aligned = { #include <asm/syscalls_64.h> }; |