Lines Matching +full:alternative +full:- +full:a

1 /* SPDX-License-Identifier: GPL-2.0 */
8 #include <asm/alternative.h>
9 #include <asm/asm-offsets.h>
10 #include <asm/nospec-branch.h>
53  * Worse, you can only have a single EXPORT_SYMBOL per line,
64 #include <asm/GEN-for-each-reg.h>
71 #include <asm/GEN-for-each-reg.h>
93 #include <asm/GEN-for-each-reg.h>
100 #include <asm/GEN-for-each-reg.h>
119 #include <asm/GEN-for-each-reg.h>
126 #include <asm/GEN-for-each-reg.h>
135  * compiler issues is either a short one or the compiler doesn't use
136  * relocations for same-section JMPs and that breaks the returns
147  * - srso_alias_untrain_ret() is 2M aligned
148  * - srso_alias_safe_ret() is also in the same 2M page but bits 2, 8, 14
156  * As a result, srso_alias_safe_ret() becomes a safe return.
188  * above. On kernel entry, srso_untrain_ret() is executed which is a
193  * later, it is a stack manipulation and a RET which is mispredicted and
194  * thus a "safe" one to use.
197 	.skip 64 - (srso_safe_ret - srso_untrain_ret), 0xcc
203  * This forces the function return instruction to speculate into a trap
229 /* Dummy for the alternative in CALL_UNTRAIN_RET. */
254  * Regarding alignment - the instructions which need to be untrained,
255  * must all start at a cacheline boundary for Zen1/2 generations. That
258  * must start at a cacheline boundary.
263  * 1) The RET at retbleed_return_thunk must be on a 64 byte boundary, for
268  *    from re-poisioning the BTB prediction.
271 	.skip 64 - (retbleed_return_thunk - retbleed_untrain_ret), 0xcc
281 	 * Executing the TEST instruction has a side effect of evicting any BTB
288 	 * As executed from retbleed_return_thunk, this is a plain RET.
293 	 * This creates a correct BTB prediction (type=ret), but in the
297 	 * With SMT enabled and STIBP active, a sibling thread cannot poison
298 	 * RET's prediction to a type of its choice, but can evict the
329 	ALTERNATIVE JMP_RETBLEED_UNTRAIN_RET, JMP_SRSO_UNTRAIN_RET, X86_FEATURE_SRSO
341 	 * Keep the hotpath in a 16byte I-fetch for the non-debug
370  * This function name is magical and is used by -mfunction-return=thunk-extern
377  * The ALTERNATIVE below adds a really loud warning to catch the case
388 	ALTERNATIVE __stringify(ANNOTATE_UNRET_SAFE; ret), \