On Thu, Jul 06, 2017 at 02:12:37PM +0100, Maciej W. Rozycki wrote: > On Thu, 6 Jul 2017, James Hogan wrote: > > > (and would have to forcibly use the 32-bit encoding in the microMIPS > > > case)? > > > > I don't believe there is a 16-bit SYSCALL encoding in microMIPS, at > > least I can't see one in the 5.04 manual. > > I referred to the preceding instruction, presumably LI, that does have a > 16-bit variant in the microMIPS instruction set. Ah yes, I see what you mean. Hopefully microMIPS support is new enough for that not to matter. It appears that the restart behaviour was improved in v2.6.36 in commit 8f5a00eb422e ("MIPS: Sanitize restart logics"), whereas first mentions of micromips are in v3.9, in commit f8fa4811dbb2 ("MIPS: Add support for the M14KEc core."). Cheers James