linux_dsm_epyc7002/arch/mips/lib
Maciej W. Rozycki c4fca4fdea MIPS: strnlen_user.S: Fix a CPU_DADDI_WORKAROUNDS regression
Correct a regression introduced with 8453eebd [MIPS: Fix strnlen_user()
return value in case of overlong strings.] causing assembler warnings
and broken code generated in __strnlen_kernel_nocheck_asm:

arch/mips/lib/strnlen_user.S: Assembler messages:
arch/mips/lib/strnlen_user.S:64: Warning: Macro instruction expanded into multiple instructions in a branch delay slot

with the CPU_DADDI_WORKAROUNDS option set, resulting in the function
looping indefinitely upon mounting NFS root.

Use conditional assembly to avoid a microMIPS code size regression.
Using $at unconditionally would cause such a regression as there are no
16-bit instruction encodings available for ALU operations using this
register.  Using $v1 unconditionally would produce short microMIPS
encodings, but would prevent this register from being used across calls
to this function.

The extra LI operation introduced is free, replacing a NOP originally
scheduled into the delay slot of the branch that follows.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10205/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-05-29 20:23:58 +02:00
..
ashldi3.c
ashrdi3.c
bitops.c MIPS: Remove unneeded volatile from arch/mips/lib/bitops.c 2013-05-08 01:19:06 +02:00
cmpdi2.c [MIPS] Add __cmpdi2 2007-08-27 02:17:00 +01:00
csum_partial.S MIPS: csum_partial: Improve instruction parallelism. 2015-04-01 17:22:11 +02:00
delay.c MIPS: __delay ABI-dependent subtraction simplification 2014-05-30 21:01:08 +02:00
dump_tlb.c Revert "MIPS: Allow ASID size to be determined at boot time." 2013-05-16 20:35:42 +02:00
iomap-pci.c mips: use the the PCI controller's io_map_base 2012-01-31 23:20:30 +02:00
iomap.c MIPS: iomap: Use __mem_{read,write}{b,w,l} for MMIO 2014-11-24 07:45:42 +01:00
libgcc.h MIPS: libgcc.h: Checkpatch cleanup 2010-04-12 17:26:15 +01:00
lshrdi3.c
Makefile MIPS: Use generic checksum functions for MIPS R6 2015-02-17 15:37:19 +00:00
memcpy.S MIPS: lib: memcpy: Add MIPS R6 support 2015-02-17 15:37:29 +00:00
memset.S MIPS: lib: memset: Add MIPS R6 support 2015-02-17 15:37:30 +00:00
mips-atomic.c MIPS: asm: irqflags: Add MIPS R6 related definitions 2015-02-17 15:37:20 +00:00
r3k_dump_tlb.c MIPS: R3000: Remove redundant parentheses 2014-11-24 07:45:01 +01:00
strlen_user.S MIPS: Remove __strlen_user(). 2014-11-24 07:45:00 +01:00
strncpy_user.S MIPS: __strncpy_from_user_asm CPU_DADDI_WORKAROUNDS bug fix 2014-05-13 00:29:38 +02:00
strnlen_user.S MIPS: strnlen_user.S: Fix a CPU_DADDI_WORKAROUNDS regression 2015-05-29 20:23:58 +02:00
ucmpdi2.c [MIPS] Export __ucmpdi2 to modules. 2008-03-12 14:14:41 +00:00
uncached.c mips: delete non-required instances of include <linux/init.h> 2014-01-24 22:39:56 +01:00