powerpc/tm/tm-poison.c

1 // SPDX-License-Identifier: GPL-2.0-only
11  * present child's poison will leak into parent's f31 or vr31 registers,
12  * otherwise, poison will never leak into parent's f31 and vr31 registers.
74 		 * The Time Base (TB) is a 64-bit counter register that is  in tm_poison_test()
81 		 * to r6. When r7 (current) - r6 (initial) > 61440000000 we bail  in tm_poison_test()
90 		"1:     mfspr   7, 268          ;" // r7 (TB current)  in tm_poison_test()
91 		"       subf    7, 6, 7         ;" // r7 - r6 > 61440000000 ?  in tm_poison_test()
102 		"       bne     2f              ;" // broken :-(  in tm_poison_test()
114 	 * On leak 'unknown' will contain 'poison' value from child,  in tm_poison_test()
115 	 * otherwise (no leak) 'unknown' will contain the same value  in tm_poison_test()
116 	 * as r3 before entering in transactional mode, i.e. 0x1.  in tm_poison_test()
138 		"1:     mfspr   7, 268          ;" // r7 (TB current)  in tm_poison_test()
139 		"       subf    7, 6, 7         ;" // r7 - r6 > 61440000000 ?  in tm_poison_test()
150 		"       bne     2f              ;" // broken :-(  in tm_poison_test()
162 	 * On leak 'unknown' will contain 'poison' value from child,  in tm_poison_test()
163 	 * otherwise (no leak) 'unknown' will contain the same value  in tm_poison_test()
164 	 * as r3 before entering in transactional mode, i.e. 0x1.  in tm_poison_test()