[PATCH] x86: Allow disabling early pci scans with pci=noearly or disallowing conf1

Some buggy systems can machine check when config space accesses
happen for some non existent devices.  i386/x86-64 do some early
device scans that might trigger this. Allow pci=noearly to disable
this. Also when type 1 is disabling also don't do any early
accesses which are always type1.

This moves the pci= configuration parsing to be a early parameter.
I don't think this can break anything because it only changes
a single global that is only used by PCI.

Cc: gregkh@suse.de
Cc: Trammell Hudson <hudson@osresearch.net>

Signed-off-by: Andi Kleen <ak@suse.de>

1 files changed, 4 insertions, 0 deletions

diff --git a/arch/x86_64/kernel/early-quirks.c b/arch/x86_64/kernel/early-quirks.c
index d637cff1c4b..208e38a372c 100644
--- a/arch/x86_64/kernel/early-quirks.c
+++ b/arch/x86_64/kernel/early-quirks.c
@@ -82,6 +82,10 @@ static struct chipset early_qrk[] = {
 void __init early_quirks(void)
 {
         int num, slot, func;
+
+        if (!early_pci_allowed())
+                return;
+
         /* Poor man's PCI discovery */
         for (num = 0; num < 32; num++) {
                 for (slot = 0; slot < 32; slot++) {