Add a redzone between the pcb and the stack. Sent to port-amd64@.

disable CTASSERT for lint

Rewrite the FPU code on x86. This greatly simplifies the logic and removes
the dependency on IPL_HIGH. NVMM is updated accordingly. Posted on
port-amd64 a week ago.

Bump the kernel version to 9.99.16.

Rework dbregs, to switch the registers during context switches, and not on
each user->kernel transition via userret. Reloads of DR6/DR7 are expensive
on both native and xen.

branches: 1.28.2; 1.28.4;
gc unused

Don't embed our own values in the reserved fields of the XSAVE area, it
really is a bad idea. Move them into the PCB.

Introduce PT_GETDBREGS and PT_SETDBREGS in ptrace(2) on i386 and amd64

This interface is modeled after FreeBSD API with the usage.

This replaced previous watchpoint API. The previous one was introduced
recently in NetBSD-current and remove its spurs without any
backward-compatibility.

Design choices for Debug Register accessors:
- exec() (TRAP_EXEC event) must remove debug registers from LWP
- debug registers are only per-LWP, not per-process globally
- debug registers must not be inherited after (v)forking a process
- debug registers must not be inherited after forking a thread
- a debugger is responsible to set global watchpoints/breakpoints with the
debug registers, to achieve this PTRACE_LWP_CREATE/PTRACE_LWP_EXIT event
monitoring function is designed to be used
- debug register traps must generate SIGTRAP with si_code TRAP_DBREG
- debugger is responsible to retrieve debug register state to distinguish
the exact debug register trap (DR6 is Status Register on x86)
- kernel must not remove debug register traps after triggering a trap event
a debugger is responsible to detach this trap with appropriate PT_SETDBREGS
call (DR7 is Control Register on x86)
- debug registers must not be exposed in mcontext
- userland must not be allowed to set a trap on the kernel

Implementation notes on i386 and amd64:
- the initial state of debug register is retrieved on boot and this value is
stored in a local copy (initdbregs), this value is used to initialize dbreg
context after PT_GETDBREGS
- struct dbregs is stored in pcb as a pointer and by default not initialized
- reserved registers (DR4-DR5, DR9-DR15) are ignored

Further ideas:
- restrict this interface with securelevel

Tested on real hardware i386 (Intel Pentium IV) and amd64 (Intel i7).

This commit enables 390 debug register ATF tests in kernel/arch/x86.
All tests are passing.

This commit does not cover netbsd32 compat code. Currently other interface
PT_GET_SIGINFO/PT_SET_SIGINFO is required in netbsd32 compat code in order to
validate reliably PT_GETDBREGS/PT_SETDBREGS.

This implementation does not cover FreeBSD specific defines in their
<x86/reg.h>: DBREG_DR7_LOCAL_ENABLE, DBREG_DR7_GLOBAL_ENABLE, DBREG_DR7_LEN_1
etc. These values tend to be reinvented by each tracer on its own. GNU
Debugger (GDB) works with NetBSD debug registers after adding this patch:

--- gdb/amd64bsd-nat.c.orig 2016-02-10 03:19:39.000000000 +0000
+++ gdb/amd64bsd-nat.c
@@ -167,6 +167,10 @@ amd64bsd_target (void)

#ifdef HAVE_PT_GETDBREGS

+#ifndef DBREG_DRX
+#define DBREG_DRX(d,x) ((d)->dr[(x)])
+#endif
+
static unsigned long
amd64bsd_dr_get (ptid_t ptid, int regnum)
{


Another reason to stop introducing unpopular defines covering machine
specific register macros is that these value varies across generations of
the same CPU family.

GDB demo:
(gdb) c
Continuing.

Watchpoint 2: traceme

Old value = 0
New value = 16
main (argc=1, argv=0x7f7fff79fe30) at test.c:8
8 printf("traceme=%d\n", traceme);

(Currently the GDB interface is not reliable due to NetBSD support bugs)

Sponsored by <The NetBSD Foundation>

branches: 1.25.6; 1.25.10; 1.25.14;
Move the amd64 and i386 pcb to the bottom of the uarea, and move the
kernel stack to the top.
Change the pcb layouts so that fpu save area is at the end and is
64byte aligned ready for xsave (saving the ymm registers).
Welcome to 6.99.32

Move sys/arch/amd64/amd64/fpu.c and sys/arch/amd64/include/fpu.h
into sys/arch/x86 in preparation for using the same code for i386.

Convert the amd64 build to use x86/cpu_extended_state.h so that the fpu
definitions match those of i386.
Mostly just structure and field renames, in addition:
1) process_xmm_to_s87() and process_s87_to_xmm() moved into
x86/convert_xmm_s87.c so they can be used by amd64's netbsd32 code.
2) The linux signal code simplified to use a structure copy for ths fxsave
data - it matches the hardware definition and won't change.

Remove the unused 'struct md_coredump'.

Remove the fields that were used to save the i387 fp state on interrupt.
They were written but never read.
Possibly they should be saved for 32 bit processes, but that might be a relic
from real i387 where the fpu was actully asynchronous.

revert fpu/pcu changes until we figure out what's wrong; they cause random
freezes

Use the MI "pcu" framework for bookkeeping of npx/fpu states on x86.
This reduces the amount of MD code enormously, and makes it easier
to implement support for newer CPU features which require more fpu
state, or for fpu usage by the kernel.
For access to FPU state across CPUs, an xcall kthread is used now
rather than a dedicated IPI.
No user visible changes intended.

branches: 1.18.2;
Move the two fields used to save some i387 state on the last fpu trap
into their own sub-structure of the pcb (from 'struct savefpu').
They only (seem) to be used in some code that generates core dumps
for 32bit processes (code that might be broken as well!).
'struct safefpu' is now identical to 'struct fxsave64'. One (or both)
needs extending to support AVX - might need to be dynamically sized.
Removed all the __aligned(16) except for the one in struct pcb itself.
Only the copy used for the fsave instruction need be aligned.

branches: 1.17.8; 1.17.18;
add the guts of TLS support on amd64. based on joerg's patch,
reworked by me to support 32-bit processes as well.
we now keep %fs and %gs loaded with the user values
while in the kernel, which means we don't need to
reload them when returning to user mode.

branches: 1.16.2; 1.16.4;
Make pcb_ldt_sel, in amd64, an unused field. Unlike in i386, it was
missed during clean-up of LDT handling.

branches: 1.15.8;
put the contents of these header files around #ifdef __x86_64__, and
#include the <i386/foo.h> in the #else clause, making these files
largely bit-size independant.

branches: 1.14.6;
lcr0() was changed to take a u_long. pcb_cr0 was a 32-bit signed quantity.
It was being sign extended in cpu_hatch() (CR0_PG is always set), causing
systems to crash and reboot before going multiuser.

Remove clause 3 and 4 from TNF licenses

branches: 1.12.2; 1.12.4;
use POSIX integer types

branches: 1.11.6;
- make amd64 use per-cpu tss.
- fix iopl syscall for amd64+xen.

branches: 1.10.6;
Shuffle things around so that pcb_savefpu goes back to be aligned in a 16
bit boundary. Noted by Arto Huusko.

make cr2 64 bits. Requested by fvdl.

preserve cr2 on pcb for the benefit of linux emulation.

branches: 1.7.2;
Merge the ppcoea-renovation branch to HEAD.

This branch was a major cleanup and rototill of many of the various OEA
cpu based PPC ports that focused on sharing as much code as possible
between the various ports to eliminate near-identical copies of files in
every tree. Additionally there is a new PIC system that unifies the
interface to interrupt code for all different OEA ppc arches. The work
for this branch was done by a variety of people, too long to list here.

TODO:
bebox still needs work to complete the transition to -renovation.
ofppc still needs a bunch of work, which I will be looking at.
ev64260 still needs to be renovated
amigappc was not attempted.

NOTES:
pmppc was removed as an arch, and moved to a evbppc target.

branches: 1.6.8; 1.6.10;
merge yamt-idlelwp branch. asked by core@. some ports still needs work.

from doc/BRANCHES:

idle lwp, and some changes depending on it.

1. separate context switching and thread scheduling.
(cf. gmcgarry_ctxsw)
2. implement idle lwp.
3. clean up related MD/MI interfaces.
4. make scheduler(s) modular.

branches: 1.5.2; 1.5.4; 1.5.10;
Kill caddr_t; there will be some MI fallout, but it will be fixed shortly.

branches: 1.4.26;
merge ktrace-lwp.

branches: 1.3.2;
Optionally include saving and restoring the 64bit %gs and %fs base register
values in the PCB. Do this in pmap_activate for now (XXX not a good place
for it, but a convenient one).

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22364, verified by myself.

branches: 1.1.2;
Rename the x86_64 port to amd64, as this is the actual name used for
the processor family now. x86_64 is kept as the MACHINE_ARCH value,
since it's already widely used (by e.g. the toolchain, etc), and
by other operating systems.

disable CTASSERT for lint

Rewrite the FPU code on x86. This greatly simplifies the logic and removes
the dependency on IPL_HIGH. NVMM is updated accordingly. Posted on
port-amd64 a week ago.

Bump the kernel version to 9.99.16.

Rework dbregs, to switch the registers during context switches, and not on
each user->kernel transition via userret. Reloads of DR6/DR7 are expensive
on both native and xen.

branches: 1.28.2; 1.28.4;
gc unused

Don't embed our own values in the reserved fields of the XSAVE area, it
really is a bad idea. Move them into the PCB.

Introduce PT_GETDBREGS and PT_SETDBREGS in ptrace(2) on i386 and amd64

This interface is modeled after FreeBSD API with the usage.

This replaced previous watchpoint API. The previous one was introduced
recently in NetBSD-current and remove its spurs without any
backward-compatibility.

Design choices for Debug Register accessors:
- exec() (TRAP_EXEC event) must remove debug registers from LWP
- debug registers are only per-LWP, not per-process globally
- debug registers must not be inherited after (v)forking a process
- debug registers must not be inherited after forking a thread
- a debugger is responsible to set global watchpoints/breakpoints with the
debug registers, to achieve this PTRACE_LWP_CREATE/PTRACE_LWP_EXIT event
monitoring function is designed to be used
- debug register traps must generate SIGTRAP with si_code TRAP_DBREG
- debugger is responsible to retrieve debug register state to distinguish
the exact debug register trap (DR6 is Status Register on x86)
- kernel must not remove debug register traps after triggering a trap event
a debugger is responsible to detach this trap with appropriate PT_SETDBREGS
call (DR7 is Control Register on x86)
- debug registers must not be exposed in mcontext
- userland must not be allowed to set a trap on the kernel

Implementation notes on i386 and amd64:
- the initial state of debug register is retrieved on boot and this value is
stored in a local copy (initdbregs), this value is used to initialize dbreg
context after PT_GETDBREGS
- struct dbregs is stored in pcb as a pointer and by default not initialized
- reserved registers (DR4-DR5, DR9-DR15) are ignored

Further ideas:
- restrict this interface with securelevel

Tested on real hardware i386 (Intel Pentium IV) and amd64 (Intel i7).

This commit enables 390 debug register ATF tests in kernel/arch/x86.
All tests are passing.

This commit does not cover netbsd32 compat code. Currently other interface
PT_GET_SIGINFO/PT_SET_SIGINFO is required in netbsd32 compat code in order to
validate reliably PT_GETDBREGS/PT_SETDBREGS.

This implementation does not cover FreeBSD specific defines in their
<x86/reg.h>: DBREG_DR7_LOCAL_ENABLE, DBREG_DR7_GLOBAL_ENABLE, DBREG_DR7_LEN_1
etc. These values tend to be reinvented by each tracer on its own. GNU
Debugger (GDB) works with NetBSD debug registers after adding this patch:

--- gdb/amd64bsd-nat.c.orig 2016-02-10 03:19:39.000000000 +0000
+++ gdb/amd64bsd-nat.c
@@ -167,6 +167,10 @@ amd64bsd_target (void)

#ifdef HAVE_PT_GETDBREGS

+#ifndef DBREG_DRX
+#define DBREG_DRX(d,x) ((d)->dr[(x)])
+#endif
+
static unsigned long
amd64bsd_dr_get (ptid_t ptid, int regnum)
{


Another reason to stop introducing unpopular defines covering machine
specific register macros is that these value varies across generations of
the same CPU family.

GDB demo:
(gdb) c
Continuing.

Watchpoint 2: traceme

Old value = 0
New value = 16
main (argc=1, argv=0x7f7fff79fe30) at test.c:8
8 printf("traceme=%d\n", traceme);

(Currently the GDB interface is not reliable due to NetBSD support bugs)

Sponsored by <The NetBSD Foundation>

branches: 1.25.6; 1.25.10; 1.25.14;
Move the amd64 and i386 pcb to the bottom of the uarea, and move the
kernel stack to the top.
Change the pcb layouts so that fpu save area is at the end and is
64byte aligned ready for xsave (saving the ymm registers).
Welcome to 6.99.32

Move sys/arch/amd64/amd64/fpu.c and sys/arch/amd64/include/fpu.h
into sys/arch/x86 in preparation for using the same code for i386.

Convert the amd64 build to use x86/cpu_extended_state.h so that the fpu
definitions match those of i386.
Mostly just structure and field renames, in addition:
1) process_xmm_to_s87() and process_s87_to_xmm() moved into
x86/convert_xmm_s87.c so they can be used by amd64's netbsd32 code.
2) The linux signal code simplified to use a structure copy for ths fxsave
data - it matches the hardware definition and won't change.

Remove the unused 'struct md_coredump'.

Remove the fields that were used to save the i387 fp state on interrupt.
They were written but never read.
Possibly they should be saved for 32 bit processes, but that might be a relic
from real i387 where the fpu was actully asynchronous.

revert fpu/pcu changes until we figure out what's wrong; they cause random
freezes

Use the MI "pcu" framework for bookkeeping of npx/fpu states on x86.
This reduces the amount of MD code enormously, and makes it easier
to implement support for newer CPU features which require more fpu
state, or for fpu usage by the kernel.
For access to FPU state across CPUs, an xcall kthread is used now
rather than a dedicated IPI.
No user visible changes intended.

branches: 1.18.2;
Move the two fields used to save some i387 state on the last fpu trap
into their own sub-structure of the pcb (from 'struct savefpu').
They only (seem) to be used in some code that generates core dumps
for 32bit processes (code that might be broken as well!).
'struct safefpu' is now identical to 'struct fxsave64'. One (or both)
needs extending to support AVX - might need to be dynamically sized.
Removed all the __aligned(16) except for the one in struct pcb itself.
Only the copy used for the fsave instruction need be aligned.

branches: 1.17.8; 1.17.18;
add the guts of TLS support on amd64. based on joerg's patch,
reworked by me to support 32-bit processes as well.
we now keep %fs and %gs loaded with the user values
while in the kernel, which means we don't need to
reload them when returning to user mode.

branches: 1.16.2; 1.16.4;
Make pcb_ldt_sel, in amd64, an unused field. Unlike in i386, it was
missed during clean-up of LDT handling.

branches: 1.15.8;
put the contents of these header files around #ifdef __x86_64__, and
#include the <i386/foo.h> in the #else clause, making these files
largely bit-size independant.

branches: 1.14.6;
lcr0() was changed to take a u_long. pcb_cr0 was a 32-bit signed quantity.
It was being sign extended in cpu_hatch() (CR0_PG is always set), causing
systems to crash and reboot before going multiuser.

Remove clause 3 and 4 from TNF licenses

branches: 1.12.2; 1.12.4;
use POSIX integer types

branches: 1.11.6;
- make amd64 use per-cpu tss.
- fix iopl syscall for amd64+xen.

branches: 1.10.6;
Shuffle things around so that pcb_savefpu goes back to be aligned in a 16
bit boundary. Noted by Arto Huusko.

make cr2 64 bits. Requested by fvdl.

preserve cr2 on pcb for the benefit of linux emulation.

branches: 1.7.2;
Merge the ppcoea-renovation branch to HEAD.

This branch was a major cleanup and rototill of many of the various OEA
cpu based PPC ports that focused on sharing as much code as possible
between the various ports to eliminate near-identical copies of files in
every tree. Additionally there is a new PIC system that unifies the
interface to interrupt code for all different OEA ppc arches. The work
for this branch was done by a variety of people, too long to list here.

TODO:
bebox still needs work to complete the transition to -renovation.
ofppc still needs a bunch of work, which I will be looking at.
ev64260 still needs to be renovated
amigappc was not attempted.

NOTES:
pmppc was removed as an arch, and moved to a evbppc target.

branches: 1.6.8; 1.6.10;
merge yamt-idlelwp branch. asked by core@. some ports still needs work.

from doc/BRANCHES:

idle lwp, and some changes depending on it.

1. separate context switching and thread scheduling.
(cf. gmcgarry_ctxsw)
2. implement idle lwp.
3. clean up related MD/MI interfaces.
4. make scheduler(s) modular.

branches: 1.5.2; 1.5.4; 1.5.10;
Kill caddr_t; there will be some MI fallout, but it will be fixed shortly.

branches: 1.4.26;
merge ktrace-lwp.

branches: 1.3.2;
Optionally include saving and restoring the 64bit %gs and %fs base register
values in the PCB. Do this in pmap_activate for now (XXX not a good place
for it, but a convenient one).

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22364, verified by myself.

branches: 1.1.2;
Rename the x86_64 port to amd64, as this is the actual name used for
the processor family now. x86_64 is kept as the MACHINE_ARCH value,
since it's already widely used (by e.g. the toolchain, etc), and
by other operating systems.

Rewrite the FPU code on x86. This greatly simplifies the logic and removes
the dependency on IPL_HIGH. NVMM is updated accordingly. Posted on
port-amd64 a week ago.

Bump the kernel version to 9.99.16.

Rework dbregs, to switch the registers during context switches, and not on
each user->kernel transition via userret. Reloads of DR6/DR7 are expensive
on both native and xen.

branches: 1.28.2; 1.28.4;
gc unused

Don't embed our own values in the reserved fields of the XSAVE area, it
really is a bad idea. Move them into the PCB.

Introduce PT_GETDBREGS and PT_SETDBREGS in ptrace(2) on i386 and amd64

This interface is modeled after FreeBSD API with the usage.

This replaced previous watchpoint API. The previous one was introduced
recently in NetBSD-current and remove its spurs without any
backward-compatibility.

Design choices for Debug Register accessors:
- exec() (TRAP_EXEC event) must remove debug registers from LWP
- debug registers are only per-LWP, not per-process globally
- debug registers must not be inherited after (v)forking a process
- debug registers must not be inherited after forking a thread
- a debugger is responsible to set global watchpoints/breakpoints with the
debug registers, to achieve this PTRACE_LWP_CREATE/PTRACE_LWP_EXIT event
monitoring function is designed to be used
- debug register traps must generate SIGTRAP with si_code TRAP_DBREG
- debugger is responsible to retrieve debug register state to distinguish
the exact debug register trap (DR6 is Status Register on x86)
- kernel must not remove debug register traps after triggering a trap event
a debugger is responsible to detach this trap with appropriate PT_SETDBREGS
call (DR7 is Control Register on x86)
- debug registers must not be exposed in mcontext
- userland must not be allowed to set a trap on the kernel

Implementation notes on i386 and amd64:
- the initial state of debug register is retrieved on boot and this value is
stored in a local copy (initdbregs), this value is used to initialize dbreg
context after PT_GETDBREGS
- struct dbregs is stored in pcb as a pointer and by default not initialized
- reserved registers (DR4-DR5, DR9-DR15) are ignored

Further ideas:
- restrict this interface with securelevel

Tested on real hardware i386 (Intel Pentium IV) and amd64 (Intel i7).

This commit enables 390 debug register ATF tests in kernel/arch/x86.
All tests are passing.

This commit does not cover netbsd32 compat code. Currently other interface
PT_GET_SIGINFO/PT_SET_SIGINFO is required in netbsd32 compat code in order to
validate reliably PT_GETDBREGS/PT_SETDBREGS.

This implementation does not cover FreeBSD specific defines in their
<x86/reg.h>: DBREG_DR7_LOCAL_ENABLE, DBREG_DR7_GLOBAL_ENABLE, DBREG_DR7_LEN_1
etc. These values tend to be reinvented by each tracer on its own. GNU
Debugger (GDB) works with NetBSD debug registers after adding this patch:

--- gdb/amd64bsd-nat.c.orig 2016-02-10 03:19:39.000000000 +0000
+++ gdb/amd64bsd-nat.c
@@ -167,6 +167,10 @@ amd64bsd_target (void)

#ifdef HAVE_PT_GETDBREGS

+#ifndef DBREG_DRX
+#define DBREG_DRX(d,x) ((d)->dr[(x)])
+#endif
+
static unsigned long
amd64bsd_dr_get (ptid_t ptid, int regnum)
{


Another reason to stop introducing unpopular defines covering machine
specific register macros is that these value varies across generations of
the same CPU family.

GDB demo:
(gdb) c
Continuing.

Watchpoint 2: traceme

Old value = 0
New value = 16
main (argc=1, argv=0x7f7fff79fe30) at test.c:8
8 printf("traceme=%d\n", traceme);

(Currently the GDB interface is not reliable due to NetBSD support bugs)

Sponsored by <The NetBSD Foundation>

branches: 1.25.6; 1.25.10; 1.25.14;
Move the amd64 and i386 pcb to the bottom of the uarea, and move the
kernel stack to the top.
Change the pcb layouts so that fpu save area is at the end and is
64byte aligned ready for xsave (saving the ymm registers).
Welcome to 6.99.32

Move sys/arch/amd64/amd64/fpu.c and sys/arch/amd64/include/fpu.h
into sys/arch/x86 in preparation for using the same code for i386.

Convert the amd64 build to use x86/cpu_extended_state.h so that the fpu
definitions match those of i386.
Mostly just structure and field renames, in addition:
1) process_xmm_to_s87() and process_s87_to_xmm() moved into
x86/convert_xmm_s87.c so they can be used by amd64's netbsd32 code.
2) The linux signal code simplified to use a structure copy for ths fxsave
data - it matches the hardware definition and won't change.

Remove the unused 'struct md_coredump'.

Remove the fields that were used to save the i387 fp state on interrupt.
They were written but never read.
Possibly they should be saved for 32 bit processes, but that might be a relic
from real i387 where the fpu was actully asynchronous.

revert fpu/pcu changes until we figure out what's wrong; they cause random
freezes

Use the MI "pcu" framework for bookkeeping of npx/fpu states on x86.
This reduces the amount of MD code enormously, and makes it easier
to implement support for newer CPU features which require more fpu
state, or for fpu usage by the kernel.
For access to FPU state across CPUs, an xcall kthread is used now
rather than a dedicated IPI.
No user visible changes intended.

branches: 1.18.2;
Move the two fields used to save some i387 state on the last fpu trap
into their own sub-structure of the pcb (from 'struct savefpu').
They only (seem) to be used in some code that generates core dumps
for 32bit processes (code that might be broken as well!).
'struct safefpu' is now identical to 'struct fxsave64'. One (or both)
needs extending to support AVX - might need to be dynamically sized.
Removed all the __aligned(16) except for the one in struct pcb itself.
Only the copy used for the fsave instruction need be aligned.

branches: 1.17.8; 1.17.18;
add the guts of TLS support on amd64. based on joerg's patch,
reworked by me to support 32-bit processes as well.
we now keep %fs and %gs loaded with the user values
while in the kernel, which means we don't need to
reload them when returning to user mode.

branches: 1.16.2; 1.16.4;
Make pcb_ldt_sel, in amd64, an unused field. Unlike in i386, it was
missed during clean-up of LDT handling.

branches: 1.15.8;
put the contents of these header files around #ifdef __x86_64__, and
#include the <i386/foo.h> in the #else clause, making these files
largely bit-size independant.

branches: 1.14.6;
lcr0() was changed to take a u_long. pcb_cr0 was a 32-bit signed quantity.
It was being sign extended in cpu_hatch() (CR0_PG is always set), causing
systems to crash and reboot before going multiuser.

Remove clause 3 and 4 from TNF licenses

branches: 1.12.2; 1.12.4;
use POSIX integer types

branches: 1.11.6;
- make amd64 use per-cpu tss.
- fix iopl syscall for amd64+xen.

branches: 1.10.6;
Shuffle things around so that pcb_savefpu goes back to be aligned in a 16
bit boundary. Noted by Arto Huusko.

make cr2 64 bits. Requested by fvdl.

preserve cr2 on pcb for the benefit of linux emulation.

branches: 1.7.2;
Merge the ppcoea-renovation branch to HEAD.

This branch was a major cleanup and rototill of many of the various OEA
cpu based PPC ports that focused on sharing as much code as possible
between the various ports to eliminate near-identical copies of files in
every tree. Additionally there is a new PIC system that unifies the
interface to interrupt code for all different OEA ppc arches. The work
for this branch was done by a variety of people, too long to list here.

TODO:
bebox still needs work to complete the transition to -renovation.
ofppc still needs a bunch of work, which I will be looking at.
ev64260 still needs to be renovated
amigappc was not attempted.

NOTES:
pmppc was removed as an arch, and moved to a evbppc target.

branches: 1.6.8; 1.6.10;
merge yamt-idlelwp branch. asked by core@. some ports still needs work.

from doc/BRANCHES:

idle lwp, and some changes depending on it.

1. separate context switching and thread scheduling.
(cf. gmcgarry_ctxsw)
2. implement idle lwp.
3. clean up related MD/MI interfaces.
4. make scheduler(s) modular.

branches: 1.5.2; 1.5.4; 1.5.10;
Kill caddr_t; there will be some MI fallout, but it will be fixed shortly.

branches: 1.4.26;
merge ktrace-lwp.

branches: 1.3.2;
Optionally include saving and restoring the 64bit %gs and %fs base register
values in the PCB. Do this in pmap_activate for now (XXX not a good place
for it, but a convenient one).

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22364, verified by myself.

branches: 1.1.2;
Rename the x86_64 port to amd64, as this is the actual name used for
the processor family now. x86_64 is kept as the MACHINE_ARCH value,
since it's already widely used (by e.g. the toolchain, etc), and
by other operating systems.

Rework dbregs, to switch the registers during context switches, and not on
each user->kernel transition via userret. Reloads of DR6/DR7 are expensive
on both native and xen.

branches: 1.28.2;
gc unused

Don't embed our own values in the reserved fields of the XSAVE area, it
really is a bad idea. Move them into the PCB.

Introduce PT_GETDBREGS and PT_SETDBREGS in ptrace(2) on i386 and amd64

This interface is modeled after FreeBSD API with the usage.

This replaced previous watchpoint API. The previous one was introduced
recently in NetBSD-current and remove its spurs without any
backward-compatibility.

Design choices for Debug Register accessors:
- exec() (TRAP_EXEC event) must remove debug registers from LWP
- debug registers are only per-LWP, not per-process globally
- debug registers must not be inherited after (v)forking a process
- debug registers must not be inherited after forking a thread
- a debugger is responsible to set global watchpoints/breakpoints with the
debug registers, to achieve this PTRACE_LWP_CREATE/PTRACE_LWP_EXIT event
monitoring function is designed to be used
- debug register traps must generate SIGTRAP with si_code TRAP_DBREG
- debugger is responsible to retrieve debug register state to distinguish
the exact debug register trap (DR6 is Status Register on x86)
- kernel must not remove debug register traps after triggering a trap event
a debugger is responsible to detach this trap with appropriate PT_SETDBREGS
call (DR7 is Control Register on x86)
- debug registers must not be exposed in mcontext
- userland must not be allowed to set a trap on the kernel

Implementation notes on i386 and amd64:
- the initial state of debug register is retrieved on boot and this value is
stored in a local copy (initdbregs), this value is used to initialize dbreg
context after PT_GETDBREGS
- struct dbregs is stored in pcb as a pointer and by default not initialized
- reserved registers (DR4-DR5, DR9-DR15) are ignored

Further ideas:
- restrict this interface with securelevel

Tested on real hardware i386 (Intel Pentium IV) and amd64 (Intel i7).

This commit enables 390 debug register ATF tests in kernel/arch/x86.
All tests are passing.

This commit does not cover netbsd32 compat code. Currently other interface
PT_GET_SIGINFO/PT_SET_SIGINFO is required in netbsd32 compat code in order to
validate reliably PT_GETDBREGS/PT_SETDBREGS.

This implementation does not cover FreeBSD specific defines in their
<x86/reg.h>: DBREG_DR7_LOCAL_ENABLE, DBREG_DR7_GLOBAL_ENABLE, DBREG_DR7_LEN_1
etc. These values tend to be reinvented by each tracer on its own. GNU
Debugger (GDB) works with NetBSD debug registers after adding this patch:

--- gdb/amd64bsd-nat.c.orig 2016-02-10 03:19:39.000000000 +0000
+++ gdb/amd64bsd-nat.c
@@ -167,6 +167,10 @@ amd64bsd_target (void)

#ifdef HAVE_PT_GETDBREGS

+#ifndef DBREG_DRX
+#define DBREG_DRX(d,x) ((d)->dr[(x)])
+#endif
+
static unsigned long
amd64bsd_dr_get (ptid_t ptid, int regnum)
{


Another reason to stop introducing unpopular defines covering machine
specific register macros is that these value varies across generations of
the same CPU family.

GDB demo:
(gdb) c
Continuing.

Watchpoint 2: traceme

Old value = 0
New value = 16
main (argc=1, argv=0x7f7fff79fe30) at test.c:8
8 printf("traceme=%d\n", traceme);

(Currently the GDB interface is not reliable due to NetBSD support bugs)

Sponsored by <The NetBSD Foundation>

branches: 1.25.6; 1.25.10; 1.25.14;
Move the amd64 and i386 pcb to the bottom of the uarea, and move the
kernel stack to the top.
Change the pcb layouts so that fpu save area is at the end and is
64byte aligned ready for xsave (saving the ymm registers).
Welcome to 6.99.32

Move sys/arch/amd64/amd64/fpu.c and sys/arch/amd64/include/fpu.h
into sys/arch/x86 in preparation for using the same code for i386.

Convert the amd64 build to use x86/cpu_extended_state.h so that the fpu
definitions match those of i386.
Mostly just structure and field renames, in addition:
1) process_xmm_to_s87() and process_s87_to_xmm() moved into
x86/convert_xmm_s87.c so they can be used by amd64's netbsd32 code.
2) The linux signal code simplified to use a structure copy for ths fxsave
data - it matches the hardware definition and won't change.

Remove the unused 'struct md_coredump'.

Remove the fields that were used to save the i387 fp state on interrupt.
They were written but never read.
Possibly they should be saved for 32 bit processes, but that might be a relic
from real i387 where the fpu was actully asynchronous.

revert fpu/pcu changes until we figure out what's wrong; they cause random
freezes

Use the MI "pcu" framework for bookkeeping of npx/fpu states on x86.
This reduces the amount of MD code enormously, and makes it easier
to implement support for newer CPU features which require more fpu
state, or for fpu usage by the kernel.
For access to FPU state across CPUs, an xcall kthread is used now
rather than a dedicated IPI.
No user visible changes intended.

branches: 1.18.2;
Move the two fields used to save some i387 state on the last fpu trap
into their own sub-structure of the pcb (from 'struct savefpu').
They only (seem) to be used in some code that generates core dumps
for 32bit processes (code that might be broken as well!).
'struct safefpu' is now identical to 'struct fxsave64'. One (or both)
needs extending to support AVX - might need to be dynamically sized.
Removed all the __aligned(16) except for the one in struct pcb itself.
Only the copy used for the fsave instruction need be aligned.

branches: 1.17.8; 1.17.18;
add the guts of TLS support on amd64. based on joerg's patch,
reworked by me to support 32-bit processes as well.
we now keep %fs and %gs loaded with the user values
while in the kernel, which means we don't need to
reload them when returning to user mode.

branches: 1.16.2; 1.16.4;
Make pcb_ldt_sel, in amd64, an unused field. Unlike in i386, it was
missed during clean-up of LDT handling.

branches: 1.15.8;
put the contents of these header files around #ifdef __x86_64__, and
#include the <i386/foo.h> in the #else clause, making these files
largely bit-size independant.

branches: 1.14.6;
lcr0() was changed to take a u_long. pcb_cr0 was a 32-bit signed quantity.
It was being sign extended in cpu_hatch() (CR0_PG is always set), causing
systems to crash and reboot before going multiuser.

Remove clause 3 and 4 from TNF licenses

branches: 1.12.2; 1.12.4;
use POSIX integer types

branches: 1.11.6;
- make amd64 use per-cpu tss.
- fix iopl syscall for amd64+xen.

branches: 1.10.6;
Shuffle things around so that pcb_savefpu goes back to be aligned in a 16
bit boundary. Noted by Arto Huusko.

make cr2 64 bits. Requested by fvdl.

preserve cr2 on pcb for the benefit of linux emulation.

branches: 1.7.2;
Merge the ppcoea-renovation branch to HEAD.

This branch was a major cleanup and rototill of many of the various OEA
cpu based PPC ports that focused on sharing as much code as possible
between the various ports to eliminate near-identical copies of files in
every tree. Additionally there is a new PIC system that unifies the
interface to interrupt code for all different OEA ppc arches. The work
for this branch was done by a variety of people, too long to list here.

TODO:
bebox still needs work to complete the transition to -renovation.
ofppc still needs a bunch of work, which I will be looking at.
ev64260 still needs to be renovated
amigappc was not attempted.

NOTES:
pmppc was removed as an arch, and moved to a evbppc target.

branches: 1.6.8; 1.6.10;
merge yamt-idlelwp branch. asked by core@. some ports still needs work.

from doc/BRANCHES:

idle lwp, and some changes depending on it.

1. separate context switching and thread scheduling.
(cf. gmcgarry_ctxsw)
2. implement idle lwp.
3. clean up related MD/MI interfaces.
4. make scheduler(s) modular.

branches: 1.5.2; 1.5.4; 1.5.10;
Kill caddr_t; there will be some MI fallout, but it will be fixed shortly.

branches: 1.4.26;
merge ktrace-lwp.

branches: 1.3.2;
Optionally include saving and restoring the 64bit %gs and %fs base register
values in the PCB. Do this in pmap_activate for now (XXX not a good place
for it, but a convenient one).

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22364, verified by myself.

branches: 1.1.2;
Rename the x86_64 port to amd64, as this is the actual name used for
the processor family now. x86_64 is kept as the MACHINE_ARCH value,
since it's already widely used (by e.g. the toolchain, etc), and
by other operating systems.

gc unused

Don't embed our own values in the reserved fields of the XSAVE area, it
really is a bad idea. Move them into the PCB.

Introduce PT_GETDBREGS and PT_SETDBREGS in ptrace(2) on i386 and amd64

This interface is modeled after FreeBSD API with the usage.

This replaced previous watchpoint API. The previous one was introduced
recently in NetBSD-current and remove its spurs without any
backward-compatibility.

Design choices for Debug Register accessors:
- exec() (TRAP_EXEC event) must remove debug registers from LWP
- debug registers are only per-LWP, not per-process globally
- debug registers must not be inherited after (v)forking a process
- debug registers must not be inherited after forking a thread
- a debugger is responsible to set global watchpoints/breakpoints with the
debug registers, to achieve this PTRACE_LWP_CREATE/PTRACE_LWP_EXIT event
monitoring function is designed to be used
- debug register traps must generate SIGTRAP with si_code TRAP_DBREG
- debugger is responsible to retrieve debug register state to distinguish
the exact debug register trap (DR6 is Status Register on x86)
- kernel must not remove debug register traps after triggering a trap event
a debugger is responsible to detach this trap with appropriate PT_SETDBREGS
call (DR7 is Control Register on x86)
- debug registers must not be exposed in mcontext
- userland must not be allowed to set a trap on the kernel

Implementation notes on i386 and amd64:
- the initial state of debug register is retrieved on boot and this value is
stored in a local copy (initdbregs), this value is used to initialize dbreg
context after PT_GETDBREGS
- struct dbregs is stored in pcb as a pointer and by default not initialized
- reserved registers (DR4-DR5, DR9-DR15) are ignored

Further ideas:
- restrict this interface with securelevel

Tested on real hardware i386 (Intel Pentium IV) and amd64 (Intel i7).

This commit enables 390 debug register ATF tests in kernel/arch/x86.
All tests are passing.

This commit does not cover netbsd32 compat code. Currently other interface
PT_GET_SIGINFO/PT_SET_SIGINFO is required in netbsd32 compat code in order to
validate reliably PT_GETDBREGS/PT_SETDBREGS.

This implementation does not cover FreeBSD specific defines in their
<x86/reg.h>: DBREG_DR7_LOCAL_ENABLE, DBREG_DR7_GLOBAL_ENABLE, DBREG_DR7_LEN_1
etc. These values tend to be reinvented by each tracer on its own. GNU
Debugger (GDB) works with NetBSD debug registers after adding this patch:

--- gdb/amd64bsd-nat.c.orig 2016-02-10 03:19:39.000000000 +0000
+++ gdb/amd64bsd-nat.c
@@ -167,6 +167,10 @@ amd64bsd_target (void)

#ifdef HAVE_PT_GETDBREGS

+#ifndef DBREG_DRX
+#define DBREG_DRX(d,x) ((d)->dr[(x)])
+#endif
+
static unsigned long
amd64bsd_dr_get (ptid_t ptid, int regnum)
{


Another reason to stop introducing unpopular defines covering machine
specific register macros is that these value varies across generations of
the same CPU family.

GDB demo:
(gdb) c
Continuing.

Watchpoint 2: traceme

Old value = 0
New value = 16
main (argc=1, argv=0x7f7fff79fe30) at test.c:8
8 printf("traceme=%d\n", traceme);

(Currently the GDB interface is not reliable due to NetBSD support bugs)

Sponsored by <The NetBSD Foundation>

branches: 1.25.6; 1.25.10; 1.25.14;
Move the amd64 and i386 pcb to the bottom of the uarea, and move the
kernel stack to the top.
Change the pcb layouts so that fpu save area is at the end and is
64byte aligned ready for xsave (saving the ymm registers).
Welcome to 6.99.32

Move sys/arch/amd64/amd64/fpu.c and sys/arch/amd64/include/fpu.h
into sys/arch/x86 in preparation for using the same code for i386.

Convert the amd64 build to use x86/cpu_extended_state.h so that the fpu
definitions match those of i386.
Mostly just structure and field renames, in addition:
1) process_xmm_to_s87() and process_s87_to_xmm() moved into
x86/convert_xmm_s87.c so they can be used by amd64's netbsd32 code.
2) The linux signal code simplified to use a structure copy for ths fxsave
data - it matches the hardware definition and won't change.

Remove the unused 'struct md_coredump'.

Remove the fields that were used to save the i387 fp state on interrupt.
They were written but never read.
Possibly they should be saved for 32 bit processes, but that might be a relic
from real i387 where the fpu was actully asynchronous.

revert fpu/pcu changes until we figure out what's wrong; they cause random
freezes

Use the MI "pcu" framework for bookkeeping of npx/fpu states on x86.
This reduces the amount of MD code enormously, and makes it easier
to implement support for newer CPU features which require more fpu
state, or for fpu usage by the kernel.
For access to FPU state across CPUs, an xcall kthread is used now
rather than a dedicated IPI.
No user visible changes intended.

branches: 1.18.2;
Move the two fields used to save some i387 state on the last fpu trap
into their own sub-structure of the pcb (from 'struct savefpu').
They only (seem) to be used in some code that generates core dumps
for 32bit processes (code that might be broken as well!).
'struct safefpu' is now identical to 'struct fxsave64'. One (or both)
needs extending to support AVX - might need to be dynamically sized.
Removed all the __aligned(16) except for the one in struct pcb itself.
Only the copy used for the fsave instruction need be aligned.

branches: 1.17.8; 1.17.18;
add the guts of TLS support on amd64. based on joerg's patch,
reworked by me to support 32-bit processes as well.
we now keep %fs and %gs loaded with the user values
while in the kernel, which means we don't need to
reload them when returning to user mode.

branches: 1.16.2; 1.16.4;
Make pcb_ldt_sel, in amd64, an unused field. Unlike in i386, it was
missed during clean-up of LDT handling.

branches: 1.15.8;
put the contents of these header files around #ifdef __x86_64__, and
#include the <i386/foo.h> in the #else clause, making these files
largely bit-size independant.

branches: 1.14.6;
lcr0() was changed to take a u_long. pcb_cr0 was a 32-bit signed quantity.
It was being sign extended in cpu_hatch() (CR0_PG is always set), causing
systems to crash and reboot before going multiuser.

Remove clause 3 and 4 from TNF licenses

branches: 1.12.2; 1.12.4;
use POSIX integer types

branches: 1.11.6;
- make amd64 use per-cpu tss.
- fix iopl syscall for amd64+xen.

branches: 1.10.6;
Shuffle things around so that pcb_savefpu goes back to be aligned in a 16
bit boundary. Noted by Arto Huusko.

make cr2 64 bits. Requested by fvdl.

preserve cr2 on pcb for the benefit of linux emulation.

branches: 1.7.2;
Merge the ppcoea-renovation branch to HEAD.

This branch was a major cleanup and rototill of many of the various OEA
cpu based PPC ports that focused on sharing as much code as possible
between the various ports to eliminate near-identical copies of files in
every tree. Additionally there is a new PIC system that unifies the
interface to interrupt code for all different OEA ppc arches. The work
for this branch was done by a variety of people, too long to list here.

TODO:
bebox still needs work to complete the transition to -renovation.
ofppc still needs a bunch of work, which I will be looking at.
ev64260 still needs to be renovated
amigappc was not attempted.

NOTES:
pmppc was removed as an arch, and moved to a evbppc target.

branches: 1.6.8; 1.6.10;
merge yamt-idlelwp branch. asked by core@. some ports still needs work.

from doc/BRANCHES:

idle lwp, and some changes depending on it.

1. separate context switching and thread scheduling.
(cf. gmcgarry_ctxsw)
2. implement idle lwp.
3. clean up related MD/MI interfaces.
4. make scheduler(s) modular.

branches: 1.5.2; 1.5.4; 1.5.10;
Kill caddr_t; there will be some MI fallout, but it will be fixed shortly.

branches: 1.4.26;
merge ktrace-lwp.

branches: 1.3.2;
Optionally include saving and restoring the 64bit %gs and %fs base register
values in the PCB. Do this in pmap_activate for now (XXX not a good place
for it, but a convenient one).

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22364, verified by myself.

branches: 1.1.2;
Rename the x86_64 port to amd64, as this is the actual name used for
the processor family now. x86_64 is kept as the MACHINE_ARCH value,
since it's already widely used (by e.g. the toolchain, etc), and
by other operating systems.

Don't embed our own values in the reserved fields of the XSAVE area, it
really is a bad idea. Move them into the PCB.

Introduce PT_GETDBREGS and PT_SETDBREGS in ptrace(2) on i386 and amd64

This interface is modeled after FreeBSD API with the usage.

This replaced previous watchpoint API. The previous one was introduced
recently in NetBSD-current and remove its spurs without any
backward-compatibility.

Design choices for Debug Register accessors:
- exec() (TRAP_EXEC event) must remove debug registers from LWP
- debug registers are only per-LWP, not per-process globally
- debug registers must not be inherited after (v)forking a process
- debug registers must not be inherited after forking a thread
- a debugger is responsible to set global watchpoints/breakpoints with the
debug registers, to achieve this PTRACE_LWP_CREATE/PTRACE_LWP_EXIT event
monitoring function is designed to be used
- debug register traps must generate SIGTRAP with si_code TRAP_DBREG
- debugger is responsible to retrieve debug register state to distinguish
the exact debug register trap (DR6 is Status Register on x86)
- kernel must not remove debug register traps after triggering a trap event
a debugger is responsible to detach this trap with appropriate PT_SETDBREGS
call (DR7 is Control Register on x86)
- debug registers must not be exposed in mcontext
- userland must not be allowed to set a trap on the kernel

Implementation notes on i386 and amd64:
- the initial state of debug register is retrieved on boot and this value is
stored in a local copy (initdbregs), this value is used to initialize dbreg
context after PT_GETDBREGS
- struct dbregs is stored in pcb as a pointer and by default not initialized
- reserved registers (DR4-DR5, DR9-DR15) are ignored

Further ideas:
- restrict this interface with securelevel

Tested on real hardware i386 (Intel Pentium IV) and amd64 (Intel i7).

This commit enables 390 debug register ATF tests in kernel/arch/x86.
All tests are passing.

This commit does not cover netbsd32 compat code. Currently other interface
PT_GET_SIGINFO/PT_SET_SIGINFO is required in netbsd32 compat code in order to
validate reliably PT_GETDBREGS/PT_SETDBREGS.

This implementation does not cover FreeBSD specific defines in their
<x86/reg.h>: DBREG_DR7_LOCAL_ENABLE, DBREG_DR7_GLOBAL_ENABLE, DBREG_DR7_LEN_1
etc. These values tend to be reinvented by each tracer on its own. GNU
Debugger (GDB) works with NetBSD debug registers after adding this patch:

--- gdb/amd64bsd-nat.c.orig 2016-02-10 03:19:39.000000000 +0000
+++ gdb/amd64bsd-nat.c
@@ -167,6 +167,10 @@ amd64bsd_target (void)

#ifdef HAVE_PT_GETDBREGS

+#ifndef DBREG_DRX
+#define DBREG_DRX(d,x) ((d)->dr[(x)])
+#endif
+
static unsigned long
amd64bsd_dr_get (ptid_t ptid, int regnum)
{


Another reason to stop introducing unpopular defines covering machine
specific register macros is that these value varies across generations of
the same CPU family.

GDB demo:
(gdb) c
Continuing.

Watchpoint 2: traceme

Old value = 0
New value = 16
main (argc=1, argv=0x7f7fff79fe30) at test.c:8
8 printf("traceme=%d\n", traceme);

(Currently the GDB interface is not reliable due to NetBSD support bugs)

Sponsored by <The NetBSD Foundation>

branches: 1.25.6; 1.25.10; 1.25.14;
Move the amd64 and i386 pcb to the bottom of the uarea, and move the
kernel stack to the top.
Change the pcb layouts so that fpu save area is at the end and is
64byte aligned ready for xsave (saving the ymm registers).
Welcome to 6.99.32

Move sys/arch/amd64/amd64/fpu.c and sys/arch/amd64/include/fpu.h
into sys/arch/x86 in preparation for using the same code for i386.

Convert the amd64 build to use x86/cpu_extended_state.h so that the fpu
definitions match those of i386.
Mostly just structure and field renames, in addition:
1) process_xmm_to_s87() and process_s87_to_xmm() moved into
x86/convert_xmm_s87.c so they can be used by amd64's netbsd32 code.
2) The linux signal code simplified to use a structure copy for ths fxsave
data - it matches the hardware definition and won't change.

Remove the unused 'struct md_coredump'.

Remove the fields that were used to save the i387 fp state on interrupt.
They were written but never read.
Possibly they should be saved for 32 bit processes, but that might be a relic
from real i387 where the fpu was actully asynchronous.

revert fpu/pcu changes until we figure out what's wrong; they cause random
freezes

Use the MI "pcu" framework for bookkeeping of npx/fpu states on x86.
This reduces the amount of MD code enormously, and makes it easier
to implement support for newer CPU features which require more fpu
state, or for fpu usage by the kernel.
For access to FPU state across CPUs, an xcall kthread is used now
rather than a dedicated IPI.
No user visible changes intended.

branches: 1.18.2;
Move the two fields used to save some i387 state on the last fpu trap
into their own sub-structure of the pcb (from 'struct savefpu').
They only (seem) to be used in some code that generates core dumps
for 32bit processes (code that might be broken as well!).
'struct safefpu' is now identical to 'struct fxsave64'. One (or both)
needs extending to support AVX - might need to be dynamically sized.
Removed all the __aligned(16) except for the one in struct pcb itself.
Only the copy used for the fsave instruction need be aligned.

branches: 1.17.8; 1.17.18;
add the guts of TLS support on amd64. based on joerg's patch,
reworked by me to support 32-bit processes as well.
we now keep %fs and %gs loaded with the user values
while in the kernel, which means we don't need to
reload them when returning to user mode.

branches: 1.16.2; 1.16.4;
Make pcb_ldt_sel, in amd64, an unused field. Unlike in i386, it was
missed during clean-up of LDT handling.

branches: 1.15.8;
put the contents of these header files around #ifdef __x86_64__, and
#include the <i386/foo.h> in the #else clause, making these files
largely bit-size independant.

branches: 1.14.6;
lcr0() was changed to take a u_long. pcb_cr0 was a 32-bit signed quantity.
It was being sign extended in cpu_hatch() (CR0_PG is always set), causing
systems to crash and reboot before going multiuser.

Remove clause 3 and 4 from TNF licenses

branches: 1.12.2; 1.12.4;
use POSIX integer types

branches: 1.11.6;
- make amd64 use per-cpu tss.
- fix iopl syscall for amd64+xen.

branches: 1.10.6;
Shuffle things around so that pcb_savefpu goes back to be aligned in a 16
bit boundary. Noted by Arto Huusko.

make cr2 64 bits. Requested by fvdl.

preserve cr2 on pcb for the benefit of linux emulation.

branches: 1.7.2;
Merge the ppcoea-renovation branch to HEAD.

This branch was a major cleanup and rototill of many of the various OEA
cpu based PPC ports that focused on sharing as much code as possible
between the various ports to eliminate near-identical copies of files in
every tree. Additionally there is a new PIC system that unifies the
interface to interrupt code for all different OEA ppc arches. The work
for this branch was done by a variety of people, too long to list here.

TODO:
bebox still needs work to complete the transition to -renovation.
ofppc still needs a bunch of work, which I will be looking at.
ev64260 still needs to be renovated
amigappc was not attempted.

NOTES:
pmppc was removed as an arch, and moved to a evbppc target.

branches: 1.6.8; 1.6.10;
merge yamt-idlelwp branch. asked by core@. some ports still needs work.

from doc/BRANCHES:

idle lwp, and some changes depending on it.

1. separate context switching and thread scheduling.
(cf. gmcgarry_ctxsw)
2. implement idle lwp.
3. clean up related MD/MI interfaces.
4. make scheduler(s) modular.

branches: 1.5.2; 1.5.4; 1.5.10;
Kill caddr_t; there will be some MI fallout, but it will be fixed shortly.

branches: 1.4.26;
merge ktrace-lwp.

branches: 1.3.2;
Optionally include saving and restoring the 64bit %gs and %fs base register
values in the PCB. Do this in pmap_activate for now (XXX not a good place
for it, but a convenient one).

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22364, verified by myself.

branches: 1.1.2;
Rename the x86_64 port to amd64, as this is the actual name used for
the processor family now. x86_64 is kept as the MACHINE_ARCH value,
since it's already widely used (by e.g. the toolchain, etc), and
by other operating systems.

Introduce PT_GETDBREGS and PT_SETDBREGS in ptrace(2) on i386 and amd64

This interface is modeled after FreeBSD API with the usage.

This replaced previous watchpoint API. The previous one was introduced
recently in NetBSD-current and remove its spurs without any
backward-compatibility.

Design choices for Debug Register accessors:
- exec() (TRAP_EXEC event) must remove debug registers from LWP
- debug registers are only per-LWP, not per-process globally
- debug registers must not be inherited after (v)forking a process
- debug registers must not be inherited after forking a thread
- a debugger is responsible to set global watchpoints/breakpoints with the
debug registers, to achieve this PTRACE_LWP_CREATE/PTRACE_LWP_EXIT event
monitoring function is designed to be used
- debug register traps must generate SIGTRAP with si_code TRAP_DBREG
- debugger is responsible to retrieve debug register state to distinguish
the exact debug register trap (DR6 is Status Register on x86)
- kernel must not remove debug register traps after triggering a trap event
a debugger is responsible to detach this trap with appropriate PT_SETDBREGS
call (DR7 is Control Register on x86)
- debug registers must not be exposed in mcontext
- userland must not be allowed to set a trap on the kernel

Implementation notes on i386 and amd64:
- the initial state of debug register is retrieved on boot and this value is
stored in a local copy (initdbregs), this value is used to initialize dbreg
context after PT_GETDBREGS
- struct dbregs is stored in pcb as a pointer and by default not initialized
- reserved registers (DR4-DR5, DR9-DR15) are ignored

Further ideas:
- restrict this interface with securelevel

Tested on real hardware i386 (Intel Pentium IV) and amd64 (Intel i7).

This commit enables 390 debug register ATF tests in kernel/arch/x86.
All tests are passing.

This commit does not cover netbsd32 compat code. Currently other interface
PT_GET_SIGINFO/PT_SET_SIGINFO is required in netbsd32 compat code in order to
validate reliably PT_GETDBREGS/PT_SETDBREGS.

This implementation does not cover FreeBSD specific defines in their
<x86/reg.h>: DBREG_DR7_LOCAL_ENABLE, DBREG_DR7_GLOBAL_ENABLE, DBREG_DR7_LEN_1
etc. These values tend to be reinvented by each tracer on its own. GNU
Debugger (GDB) works with NetBSD debug registers after adding this patch:

--- gdb/amd64bsd-nat.c.orig 2016-02-10 03:19:39.000000000 +0000
+++ gdb/amd64bsd-nat.c
@@ -167,6 +167,10 @@ amd64bsd_target (void)

#ifdef HAVE_PT_GETDBREGS

+#ifndef DBREG_DRX
+#define DBREG_DRX(d,x) ((d)->dr[(x)])
+#endif
+
static unsigned long
amd64bsd_dr_get (ptid_t ptid, int regnum)
{


Another reason to stop introducing unpopular defines covering machine
specific register macros is that these value varies across generations of
the same CPU family.

GDB demo:
(gdb) c
Continuing.

Watchpoint 2: traceme

Old value = 0
New value = 16
main (argc=1, argv=0x7f7fff79fe30) at test.c:8
8 printf("traceme=%d\n", traceme);

(Currently the GDB interface is not reliable due to NetBSD support bugs)

Sponsored by <The NetBSD Foundation>

Move the amd64 and i386 pcb to the bottom of the uarea, and move the
kernel stack to the top.
Change the pcb layouts so that fpu save area is at the end and is
64byte aligned ready for xsave (saving the ymm registers).
Welcome to 6.99.32

Move sys/arch/amd64/amd64/fpu.c and sys/arch/amd64/include/fpu.h
into sys/arch/x86 in preparation for using the same code for i386.

Convert the amd64 build to use x86/cpu_extended_state.h so that the fpu
definitions match those of i386.
Mostly just structure and field renames, in addition:
1) process_xmm_to_s87() and process_s87_to_xmm() moved into
x86/convert_xmm_s87.c so they can be used by amd64's netbsd32 code.
2) The linux signal code simplified to use a structure copy for ths fxsave
data - it matches the hardware definition and won't change.

Remove the unused 'struct md_coredump'.

Remove the fields that were used to save the i387 fp state on interrupt.
They were written but never read.
Possibly they should be saved for 32 bit processes, but that might be a relic
from real i387 where the fpu was actully asynchronous.

revert fpu/pcu changes until we figure out what's wrong; they cause random
freezes

Use the MI "pcu" framework for bookkeeping of npx/fpu states on x86.
This reduces the amount of MD code enormously, and makes it easier
to implement support for newer CPU features which require more fpu
state, or for fpu usage by the kernel.
For access to FPU state across CPUs, an xcall kthread is used now
rather than a dedicated IPI.
No user visible changes intended.

branches: 1.18.2;
Move the two fields used to save some i387 state on the last fpu trap
into their own sub-structure of the pcb (from 'struct savefpu').
They only (seem) to be used in some code that generates core dumps
for 32bit processes (code that might be broken as well!).
'struct safefpu' is now identical to 'struct fxsave64'. One (or both)
needs extending to support AVX - might need to be dynamically sized.
Removed all the __aligned(16) except for the one in struct pcb itself.
Only the copy used for the fsave instruction need be aligned.

branches: 1.17.8; 1.17.18;
add the guts of TLS support on amd64. based on joerg's patch,
reworked by me to support 32-bit processes as well.
we now keep %fs and %gs loaded with the user values
while in the kernel, which means we don't need to
reload them when returning to user mode.

branches: 1.16.2; 1.16.4;
Make pcb_ldt_sel, in amd64, an unused field. Unlike in i386, it was
missed during clean-up of LDT handling.

branches: 1.15.8;
put the contents of these header files around #ifdef __x86_64__, and
#include the <i386/foo.h> in the #else clause, making these files
largely bit-size independant.

branches: 1.14.6;
lcr0() was changed to take a u_long. pcb_cr0 was a 32-bit signed quantity.
It was being sign extended in cpu_hatch() (CR0_PG is always set), causing
systems to crash and reboot before going multiuser.

Remove clause 3 and 4 from TNF licenses

branches: 1.12.2; 1.12.4;
use POSIX integer types

branches: 1.11.6;
- make amd64 use per-cpu tss.
- fix iopl syscall for amd64+xen.

branches: 1.10.6;
Shuffle things around so that pcb_savefpu goes back to be aligned in a 16
bit boundary. Noted by Arto Huusko.

make cr2 64 bits. Requested by fvdl.

preserve cr2 on pcb for the benefit of linux emulation.

branches: 1.7.2;
Merge the ppcoea-renovation branch to HEAD.

This branch was a major cleanup and rototill of many of the various OEA
cpu based PPC ports that focused on sharing as much code as possible
between the various ports to eliminate near-identical copies of files in
every tree. Additionally there is a new PIC system that unifies the
interface to interrupt code for all different OEA ppc arches. The work
for this branch was done by a variety of people, too long to list here.

TODO:
bebox still needs work to complete the transition to -renovation.
ofppc still needs a bunch of work, which I will be looking at.
ev64260 still needs to be renovated
amigappc was not attempted.

NOTES:
pmppc was removed as an arch, and moved to a evbppc target.

branches: 1.6.8; 1.6.10;
merge yamt-idlelwp branch. asked by core@. some ports still needs work.

from doc/BRANCHES:

idle lwp, and some changes depending on it.

1. separate context switching and thread scheduling.
(cf. gmcgarry_ctxsw)
2. implement idle lwp.
3. clean up related MD/MI interfaces.
4. make scheduler(s) modular.

branches: 1.5.2; 1.5.4; 1.5.10;
Kill caddr_t; there will be some MI fallout, but it will be fixed shortly.

branches: 1.4.26;
merge ktrace-lwp.

branches: 1.3.2;
Optionally include saving and restoring the 64bit %gs and %fs base register
values in the PCB. Do this in pmap_activate for now (XXX not a good place
for it, but a convenient one).

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22364, verified by myself.

branches: 1.1.2;
Rename the x86_64 port to amd64, as this is the actual name used for
the processor family now. x86_64 is kept as the MACHINE_ARCH value,
since it's already widely used (by e.g. the toolchain, etc), and
by other operating systems.