Change in coreboot[master]: arch/x86: Add support for catching null dereferences through debug regs

[Raul Rangel (Code Review)]

Attention is currently required from: Robert Zieba, Nico Huber, Paul Menzel, Angel Pons, Arthur Heymans, Tim Wawrzynczak, Kyösti Mälkki, Karthik Ramasubramanian.
Raul Rangel has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/63657 )

Change subject: arch/x86: Add support for catching null dereferences through debug regs
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Patch Set 12:

(11 comments)

File src/arch/x86/breakpoint.c:

https://review.coreboot.org/c/coreboot/+/63657/comment/94fb64ca_3df2dccc 
PS12, Line 44:  = { 0 }
nit: IMO you should remove this.

https://review.coreboot.org/c/coreboot/+/63657/comment/7450605e_022d6003 
PS12, Line 105: breakpoints[i].handler = NULL;
Did you want to clear the type as well?

https://review.coreboot.org/c/coreboot/+/63657/comment/13190eb3_e9208b7f 
PS12, Line 176: type
Don't you need to assign the type to res->type?

https://review.coreboot.org/c/coreboot/+/63657/comment/8154bfdb_4bb0f5af 
PS12, Line 199: breakpoints[bp].handler = NULL;
Maybe remove the clear from the allocate method?

https://review.coreboot.org/c/coreboot/+/63657/comment/59a36ee5_e34e4ac2 
PS12, Line 250: ;
;;

File src/arch/x86/exception.c:

https://review.coreboot.org/c/coreboot/+/63657/comment/6883cbab_8e685a6d 
PS12, Line 3: #include "include/arch/breakpoint.h"
Is this different than the one in line 5?

File src/arch/x86/include/arch/breakpoint.h:

https://review.coreboot.org/c/coreboot/+/63657/comment/7927dd17_26eed4d4 
PS12, Line 8: ENV_ROMSTAGE
Does this not work in bootblock?

https://review.coreboot.org/c/coreboot/+/63657/comment/19b5e0d8_c54c0c69 
PS12, Line 40: breakpoint_get_type
Does this need to be public?

https://review.coreboot.org/c/coreboot/+/63657/comment/64ccd91b_4ea15a54 
PS12, Line 49: breakpoint_is_hit
Does this need to be public?

File src/arch/x86/null_breakpoint.c:

https://review.coreboot.org/c/coreboot/+/63657/comment/7f3fafbc_1862a95c 
PS12, Line 29: int
Should we use uintptr_t?

https://review.coreboot.org/c/coreboot/+/63657/comment/635db1f7_e4bcfd99 
PS12, Line 41: 1
true