FreeBSD source tree https://cgit-dev.freebsd.org/src-test2/atom?h=stable%2F7 2010-04-01T15:17:52Z 2010-04-01T15:17:52Z Marius Strobl marius@FreeBSD.org 2010-04-01T15:17:52Z urn:sha1:d986b9eba5f3650a11fc43615a79ce0422b043fb - The firmware of Sun Fire V1280 has a misfeature of setting %wstate to 7 which corresponds to WSTATE_KMIX in OpenSolaris whenever calling into it which totally screws us even when restoring %wstate afterwards as spill/fill traps can happen while in OFW. The rather hackish OpenBSD approach of just setting the equivalent of WSTATE_KERNEL to 7 also is no option as we treat %wstate as a bit field. So in order to deal with this problem actually implement spill/fill handlers for %wstate 7 which just act as the WSTATE_KERNEL ones except of theoretically also handling 32-bit, turn off interrupts completely so we don't even take IPIs while in OFW which should ensure we only take spill/fill traps at most and restore %wstate after calling into OFW once we have taken over the trap table. While at it, actually set WSTATE_{,PROM}_KMIX before calling into OFW just like OpenSolaris does, which should at least help testing this change on non-V1280. - Remove comments referring to the %wstate usage in BSD/OS. - Remove the no longer used RSF_ALIGN_RETRY macro. - Correct some trap table addresses in comments. - Ensure %wstate is set to WSTATE_KERNEL when taking over the trap table. - Ensure PSTATE_AM is off when entering or exiting to OFW as well as that interrupts are also completely off when exiting to OFW as the firmware trap table shouldn't be used to handle our interrupts. 2002-02-25T18:37:17Z Jake Burkholder jake@FreeBSD.org 2002-02-25T18:37:17Z urn:sha1:4c4a1a19e83205b59589fd23ff083292eda2e065 window to the user stack while in a nested kernel trap. We do this for entry to the kernel from user mode, but if we get an interrupt in kernel mode while there are still user windows in the cpu, and we attempt to spill to the user stack, we may take too many nested traps and overflow the trap stack, causing a red state exception. This is needed by upcoming changes to allow the user tsb to not be locked in the tlb. Reviewed by: tmm 2001-12-29T07:12:30Z Jake Burkholder jake@FreeBSD.org 2001-12-29T07:12:30Z urn:sha1:eddb1f8617eb31dbef5b461dbc989a27453834d0 Don't include WSTATE_TRANSITION in WSTATE_NORMAL_MASK. 2001-10-20T17:08:33Z Jake Burkholder jake@FreeBSD.org 2001-10-20T17:08:33Z urn:sha1:e47e7481dbf8bad8518f9f6be59efebabdff7815 2001-09-03T23:10:45Z Jake Burkholder jake@FreeBSD.org 2001-09-03T23:10:45Z urn:sha1:880a354a4ad66e264413c7f2fe9f276cfa2acdba with user windows in kernel mode. We split the windows using %otherwin, but instead of spilling user window directly to the pcb, we attempt to spill to user space. If this fails because a stack page is not resident (or the stack is smashed), the fault handler at tl 2 will detect the situation and resume at tl 1 again where recovery code can spill to the pcb. Any windows that have been saved to the pcb will be copied out to the user stack on return from kernel mode. Add a first stab at 32 bit window handling. This uses much of the same recovery code as above because the alignment of the stack pointer is used to detect 32 bit code. Attempting to spill a 32 bit window to a 64 bit stack, or vice versa, will cause an alignment fault. The recovery code then changes the window state to vector to a 32 bit spill/fill handler and retries the faulting instruction. Add ktr traces in useful places during trap processing. Adjust comments to reflect new code and add many more.