src/sys/amd64/include, branch releng/12.2

MFC r363527: Allow swi_sched() to be called from NMI context.

2020-08-07T00:40:28Z

For purposes of handling hardware error reported via NMIs I need a way to escape NMI context, being too restrictive to do something significant. To do it this change introduces new swi_sched() flag SWI_FROMNMI, making it careful about used KPIs. On platforms allowing IPI sending from NMI context (x86 for now) it immediately wakes clk_intr_event via new IPI_SWI, otherwise it works just like SWI_DELAY.

MFC r363242:

2020-07-28T07:04:46Z

amd64: patch ffsl to use the compiler builtin

MFC 355724,360166: Software breakpoints on Intel CPUs.

2020-05-06T22:20:37Z

355724: Support software breakpoints in the debug server on Intel CPUs. - Allow the userland hypervisor to intercept breakpoint exceptions (BP#) in the guest. A new capability (VM_CAP_BPT_EXIT) is used to enable this feature. These exceptions are reported to userland via a new VM_EXITCODE_BPT that includes the length of the original breakpoint instruction. If userland wishes to pass the exception through to the guest, it must be explicitly re-injected via vm_inject_exception(). - Export VMCS_ENTRY_INST_LENGTH as a VM_REG_GUEST_ENTRY_INST_LENGTH pseudo-register. Injecting a BP# on Intel requires setting this to the length of the breakpoint instruction. AMD SVM currently ignores writes to this register (but reports success) and fails to read it. - Rework the per-vCPU state tracked by the debug server. Rather than a single 'stepping_vcpu' global, add a structure for each vCPU that tracks state about that vCPU ('stepping', 'stepped', and 'hit_swbreak'). A global 'stopped_vcpu' tracks which vCPU is currently reporting an event. Event handlers for MTRAP and breakpoint exits loop until the associated event is reported to the debugger. Breakpoint events are discarded if the breakpoint is not present when a vCPU resumes in the breakpoint handler to retry submitting the breakpoint event. - Maintain a linked-list of active breakpoints in response to the GDB 'Z0' and 'z0' packets. 360166: Add description string for VM_CAP_BPT_EXIT. While here, replace the array of mapping structures with an array of string pointers where the index is the capability value.

MFC r356296:

2020-01-09T08:29:31Z

bhyve: terminate waiting loops if thread suspension is requested. PR: 242724

MFC r355060:

2019-12-01T16:02:15Z

amd64: assert that EARLY_COUNTER does not corrupt memory.

MFC r353672:

2019-11-18T15:28:10Z

Introduce pmap_change_prot() for amd64.

MFC r354592:

2019-11-18T13:34:27Z

amd64: change r_gdt to the local variable in hammer_time().

MFC r354649:

2019-11-12T18:03:26Z

Workaround for Intel SKL002/SKL012S errata. Security: CVE-2018-12207

MFC r354095, r354118, r354132:

2019-11-09T11:55:01Z

amd64: move pcb out of kstack to struct thread.

MFC r351594 (by kib): Centralize __pcpu definitions.

2019-10-25T18:56:46Z

Many extern struct pcpu __pcpu declarations were copied/pasted in sources. The issue is that the definition is MD, but it cannot be provided by machine/pcpu.h due to actual struct pcpu defined in sys/pcpu.h later than the inclusion of machine/pcpu.h. This forced the copying when other code needed direct access to __pcpu. There is no way around it, due to machine/pcpu.h supplying part of struct pcpu fields. To work around the problem, add a new machine/pcpu_aux.h header, which should fill any needed MD definitions after struct pcpu definition is completed. This allows to remove copies of __pcpu spread around the source. Also on x86 it makes it possible to remove work arounds like OFFSETOF_CURTHREAD or clang specific warnings supressions.