Hi,
On one of my machines (Intel Xeon 2.00GHz), Kdump is broken. Second
kernel hangs during boot during ACPI initialization. I am
using 2.6.19-rc2.
It basically hangs when it tries to read from hardware whether system
is already in ACPI mode or not. It tries to read SCI_ENABLE bit from
PM1 control register.
Interestingly this phenomenon is observed only if the code is running
on a non-boot cpu (cpu id is not zero). I system crashes on cpu 0 and
second kernel is booting on cpu 0 then everything is fine.
Following is the code sequence.
acpi_early_init()
acpi_enable_subsystem()
acpi_hw_get_mode
acpi_hw_get_register
acpi_hw_register_read
acpi_hw_low_level_read
acpi_os_read_port()
In acpi_os_read_port() it tries to read port 0x804 (inw()) and then it hangs.
Any idea what's happening? Are there any dependencies of this port being
read by a boot cpu only? Any suggestions how can I debug further?
Thanks
Vivek
-
To unsubscribe from this list: send the line "unsubscribe linux-acpi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
