CMOS breakage culprit found (?)

Matthew Dillon dillon at apollo.backplane.com
Mon Nov 17 21:39:33 PST 2003


:I think I found the block of code that hoses my CMOS with an SMP kernel.
:Line 2260 of i386/i386/mp_machdep.c in start_ap() where the first
:startup IPI is done.
:
:        /* do a STARTUP IPI */
:        lapic.icr_lo = icr_lo | 0x00000600 | vector;
:        while (lapic.icr_lo & APIC_DELSTAT_MASK)
:                 /* spin */ ;
:        u_sleep(200);           /* wait ~200uS */
:
:Can someone else who has been experiencing CMOS damage verify this?
:
:-- 
:   David P. Reese, Jr.                                     daver at xxxxxxxxxxxx
:                                               http://www.gomerbud.com/daver/

    This helps a lot but there is still a large codepath that could be
    responsible... basically the AP bootstrap code.  If you've got this
    right, then something in the AP bootstrap code is corrupting CMOS.

    I will run through the AP bootstrap code and compare it against 4.x to
    see if there is anything obvious.

					-Matt
					Matthew Dillon 
					<dillon at xxxxxxxxxxxxx>





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