linux-dev - Linux kernel development work

Age	Commit message (Collapse)	Author	Files	Lines
2022-05-17	s390/alternatives: remove padding generation code	Heiko Carstens	1	-67/+9
	clang fails to handle ".if" statements in inline assembly which are heavily used in the alternatives code. To work around this remove this code, and enforce that users of alternatives must specify original and alternative instruction sequences which have identical sizes. Add a compile time check with two ".org" statements similar to arm64. In result not only clang can handle this, but also quite a lot of code can be removed. Acked-by: Vasily Gorbik <gor@linux.ibm.com> Tested-by: Nathan Chancellor <nathan@kernel.org> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Link: https://github.com/ClangBuiltLinux/linux/issues/1356 Link: https://lore.kernel.org/r/20220511120532.2228616-3-hca@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2022-03-28	s390/alternatives: avoid using jgnop mnemonic	Vasily Gorbik	1	-1/+1
	jgnop mnemonic is only available since binutils 2.36, kernel minimal required version is 2.23. Stick to brcl to avoid build errors. Reported-by: Nathan Chancellor <nathan@kernel.org> Fixes: 4afeb670710e ("s390/alternatives: use instructions instead of byte patterns") Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2022-03-27	s390/alternatives: use instructions instead of byte patterns	Heiko Carstens	1	-3/+9
	Use readable nop instructions within the code which generates the padding areas, instead of unreadable byte patterns. The generated code is identical. Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2018-03-28	s390: add assembler macros for CPU alternatives	Martin Schwidefsky	1	-0/+108
	Add a header with macros usable in assembler files to emit alternative code sequences. It works analog to the alternatives for inline assmeblies in C files, with the same restrictions and capabilities. The syntax is ALTERNATIVE "<default instructions sequence>", \ "<alternative instructions sequence>", \ "<features-bit>" and ALTERNATIVE_2 "<default instructions sequence>", \ "<alternative instructions sqeuence #1>", \ "<feature-bit #1>", "<alternative instructions sqeuence #2>", \ "<feature-bit #2>" Reviewed-by: Vasily Gorbik <gor@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>