|author||Julius Werner <firstname.lastname@example.org>||Tue Dec 03 23:29:26 2019 -0800|
|committer||Patrick Georgi <email@example.com>||Thu Dec 05 17:58:10 2019 +0000|
arm64: Print a char to UART early in exception handler Over time our printk() seems to acquire more and more features... which is nice, but it also makes it a little less robust when something goes wrong. If the wrong global is trampled by some buffer overflow, it suddenly doesn't print anymore. It would be nice to have at least some way to tell that we triggered a real exception in that case. With this patch, arm64 exceptions will print a '!' straight to the UART before trying any of the more fancy printk() stuff. It's not much but it should tell the difference between an exception and a hang and hopefully help someone dig in the right direction sooner. This violates loglevels (which is part of the point), but presumably when you have a fatal exception you shouldn't care about that anymore. Change-Id: I3b08ab86beaee55263786011caa5588d93bbc720 Signed-off-by: Julius Werner <firstname.lastname@example.org> Reviewed-on: https://review.coreboot.org/c/coreboot/+/37465 Reviewed-by: Hung-Te Lin <email@example.com> Tested-by: build bot (Jenkins) <firstname.lastname@example.org>
coreboot is a Free Software project aimed at replacing the proprietary BIOS (firmware) found in most computers. coreboot performs a little bit of hardware initialization and then executes additional boot logic, called a payload.
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