On Thu, Aug 02, 2018 at 08:16:59AM -0700, John Baldwin wrote: > On 8/2/18 5:13 AM, Ruslan Bukin wrote: > > Author: br > > Date: Thu Aug 2 12:13:52 2018 > > New Revision: 337127 > > URL: https://svnweb.freebsd.org/changeset/base/337127 > > > > Log: > > Don't overwrite tp in set_mcontext(). > > > > This makes libthr/swapcontext_test:swapcontext1 happy. > > > > Sponsored by: DARPA, AFRL > > This seems a bit odd. Is get_mcontext() not setting gp_tp correctly, or is > makecontext() not preserving it perhaps? > > In general I feel like we should be saving/restoring 'tp' in the trapframe > on kernel entry/exit like other GPRs instead of in the pcb and then > including it in 'struct reg'. This makes it possible for debuggers to > handle TLS variables more sanely (and in general we need to fix the various > struct reg in FreeBSD architectures to include TLS registers when possible, > such as adding fs_base and gs_base on x86). It would be nice if RISC-V > started off on the correct foot here.
I wanted to do this on x86, but I gave up due to the ABI issues. When FSGSBASE instructions are supported on amd64, we save base on context switch and restore on return to usermode. _______________________________________________ [email protected] mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "[email protected]"
