Merge tag 'x86_asm_for_v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm updates from Borislav Petkov:
"Two asm wrapper fixes:
- Use XORL instead of XORQ to avoid a REX prefix and save some bytes
in the .fixup section, by Uros Bizjak.
- Replace __force_order dummy variable with a memory clobber to fix
LLVM requiring a definition for former and to prevent memory
accesses from still being cached/reordered, by Arvind Sankar"
* tag 'x86_asm_for_v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/asm: Replace __force_order with a memory clobber
x86/uaccess: Use XORL %0,%0 in __get_user_asm()
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@@ -5,15 +5,6 @@
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#include "pgtable.h"
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#include "../string.h"
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/*
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* __force_order is used by special_insns.h asm code to force instruction
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* serialization.
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*
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* It is not referenced from the code, but GCC < 5 with -fPIE would fail
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* due to an undefined symbol. Define it to make these ancient GCCs work.
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*/
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unsigned long __force_order;
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#define BIOS_START_MIN 0x20000U /* 128K, less than this is insane */
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#define BIOS_START_MAX 0x9f000U /* 640K, absolute maximum */
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