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commit22375adaa0upstream. The MIPS32r2 ChaCha code has never been buildable with the clang assembler. First, clang doesn't support the 'rotl' pseudo-instruction: error: unknown instruction, did you mean: rol, rotr? Second, clang requires that both operands of the 'wsbh' instruction be explicitly given: error: too few operands for instruction To fix this, align the code with the real instruction set by (1) using the real instruction 'rotr' instead of the nonstandard pseudo- instruction 'rotl', and (2) explicitly giving both operands to 'wsbh'. To make removing the use of 'rotl' a bit easier, also remove the unnecessary special-casing for big endian CPUs at .Lchacha_mips_xor_bytes. The tail handling is actually endian-independent since it processes one byte at a time. On big endian CPUs the old code byte-swapped SAVED_X, then iterated through it in reverse order. But the byteswap and reverse iteration canceled out. Tested with chacha20poly1305-selftest in QEMU using "-M malta" with both little endian and big endian mips32r2 kernels. Fixes:49aa7c00ed("crypto: mips/chacha - import 32r2 ChaCha code from Zinc") Cc: stable@vger.kernel.org Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202505080409.EujEBwA0-lkp@intel.com/ Link: https://lore.kernel.org/r/20250619225535.679301-1-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>