Subrata Banik has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/35165 )
Change subject: cpu/intel/car: Skip stack integrity check if FSP_USES_CB_STACK is enable ......................................................................
Patch Set 2:
(2 comments)
https://review.coreboot.org/c/coreboot/+/35165/2/src/cpu/intel/car/romstage.... File src/cpu/intel/car/romstage.c:
https://review.coreboot.org/c/coreboot/+/35165/2/src/cpu/intel/car/romstage.... PS2, Line 63: if (!CONFIG(FSP_USES_CB_STACK)) {
So by this logic, the stack_guard should not be created when FSP_USES_CB_STACK is enabled either. But I would think we still want some kind of assurance that the stack hasn't been trashed. How can we make this work, Subrata, when FSP & coreboot "share" the stack? Can we get HOB size requirements so we can carve out a separate chunk of memory there exclusively for their use?
Yes, on it to know the exact requirement and documenting the same.
How do we know that FSP-S hasn't "smashed" the stack for real and overwritten all the HOBs as well?
btw, its due to FSP-M call.
https://review.coreboot.org/c/coreboot/+/35165/2/src/cpu/intel/car/romstage.... PS2, Line 67: printk(BIOS_DEBUG, "Smashed stack detected in" : "romstage!\n");
Line length limit is 96 characters, no need to split this printk message
thanks noted. i thought its 80 :)