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author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-01-13 03:31:19 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-01-13 03:31:19 +0300 |
commit | 64ad9461521b1a357846ef6cedc4bccd48a046e0 (patch) | |
tree | f134404b6c6df89198a4a2f2be6fef21af133c73 /arch/x86/include/asm/uaccess.h | |
parent | 8e5b0adeea19309c8ce0e3c9119061554973efa9 (diff) | |
parent | 9cdbeec4096804083944d05da96bbaf59a1eb4f9 (diff) | |
download | linux-64ad9461521b1a357846ef6cedc4bccd48a046e0.tar.xz |
Merge tag 'x86_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 core updates from Borislav Petkov:
- Get rid of all the .fixup sections because this generates
misleading/wrong stacktraces and confuse RELIABLE_STACKTRACE and
LIVEPATCH as the backtrace misses the function which is being fixed
up.
- Add Straight Line Speculation mitigation support which uses a new
compiler switch -mharden-sls= which sticks an INT3 after a RET or an
indirect branch in order to block speculation after them. Reportedly,
CPUs do speculate behind such insns.
- The usual set of cleanups and improvements
* tag 'x86_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits)
x86/entry_32: Fix segment exceptions
objtool: Remove .fixup handling
x86: Remove .fixup section
x86/word-at-a-time: Remove .fixup usage
x86/usercopy: Remove .fixup usage
x86/usercopy_32: Simplify __copy_user_intel_nocache()
x86/sgx: Remove .fixup usage
x86/checksum_32: Remove .fixup usage
x86/vmx: Remove .fixup usage
x86/kvm: Remove .fixup usage
x86/segment: Remove .fixup usage
x86/fpu: Remove .fixup usage
x86/xen: Remove .fixup usage
x86/uaccess: Remove .fixup usage
x86/futex: Remove .fixup usage
x86/msr: Remove .fixup usage
x86/extable: Extend extable functionality
x86/entry_32: Remove .fixup usage
x86/entry_64: Remove .fixup usage
x86/copy_mc_64: Remove .fixup usage
...
Diffstat (limited to 'arch/x86/include/asm/uaccess.h')
-rw-r--r-- | arch/x86/include/asm/uaccess.h | 39 |
1 files changed, 17 insertions, 22 deletions
diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index 8ab9e79abb2b..ac96f9b2d64b 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -352,24 +352,22 @@ do { \ "1: movl %[lowbits],%%eax\n" \ "2: movl %[highbits],%%edx\n" \ "3:\n" \ - ".section .fixup,\"ax\"\n" \ - "4: mov %[efault],%[errout]\n" \ - " xorl %%eax,%%eax\n" \ - " xorl %%edx,%%edx\n" \ - " jmp 3b\n" \ - ".previous\n" \ - _ASM_EXTABLE_UA(1b, 4b) \ - _ASM_EXTABLE_UA(2b, 4b) \ + _ASM_EXTABLE_TYPE_REG(1b, 3b, EX_TYPE_EFAULT_REG | \ + EX_FLAG_CLEAR_AX_DX, \ + %[errout]) \ + _ASM_EXTABLE_TYPE_REG(2b, 3b, EX_TYPE_EFAULT_REG | \ + EX_FLAG_CLEAR_AX_DX, \ + %[errout]) \ : [errout] "=r" (retval), \ [output] "=&A"(x) \ : [lowbits] "m" (__m(__ptr)), \ [highbits] "m" __m(((u32 __user *)(__ptr)) + 1), \ - [efault] "i" (-EFAULT), "0" (retval)); \ + "0" (retval)); \ }) #else #define __get_user_asm_u64(x, ptr, retval) \ - __get_user_asm(x, ptr, retval, "q", "=r") + __get_user_asm(x, ptr, retval, "q") #endif #define __get_user_size(x, ptr, size, retval) \ @@ -380,14 +378,14 @@ do { \ __chk_user_ptr(ptr); \ switch (size) { \ case 1: \ - __get_user_asm(x_u8__, ptr, retval, "b", "=q"); \ + __get_user_asm(x_u8__, ptr, retval, "b"); \ (x) = x_u8__; \ break; \ case 2: \ - __get_user_asm(x, ptr, retval, "w", "=r"); \ + __get_user_asm(x, ptr, retval, "w"); \ break; \ case 4: \ - __get_user_asm(x, ptr, retval, "l", "=r"); \ + __get_user_asm(x, ptr, retval, "l"); \ break; \ case 8: \ __get_user_asm_u64(x, ptr, retval); \ @@ -397,20 +395,17 @@ do { \ } \ } while (0) -#define __get_user_asm(x, addr, err, itype, ltype) \ +#define __get_user_asm(x, addr, err, itype) \ asm volatile("\n" \ "1: mov"itype" %[umem],%[output]\n" \ "2:\n" \ - ".section .fixup,\"ax\"\n" \ - "3: mov %[efault],%[errout]\n" \ - " xorl %k[output],%k[output]\n" \ - " jmp 2b\n" \ - ".previous\n" \ - _ASM_EXTABLE_UA(1b, 3b) \ + _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_EFAULT_REG | \ + EX_FLAG_CLEAR_AX, \ + %[errout]) \ : [errout] "=r" (err), \ - [output] ltype(x) \ + [output] "=a" (x) \ : [umem] "m" (__m(addr)), \ - [efault] "i" (-EFAULT), "0" (err)) + "0" (err)) #endif // CONFIG_CC_HAS_ASM_GOTO_OUTPUT |