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iommu/amd: Work around wrong IOAPIC device-id in IVRS table

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On some systems the BIOS puts the wrong device-id for the
IO-APIC into the IVRS table. The result is that interrupt
remapping is not working for the IO-APIC irqs. This usually
means a kernel panic at boot because the timer is not
working.
Fix this kernel panic by disabling interrupt remapping if
this problem is discovered in the IVRS table.

Reported-by: Andrew Oakley <andrew@ado.is-a-geek.net>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
This commit is contained in:
Joerg Roedel 2012-10-16 14:52:51 +02:00
parent ddffeb8c4d
commit c2ff5cf529
1 changed files with 32 additions and 7 deletions
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39
drivers/iommu/amd_iommu_init.c
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@ -1599,21 +1599,46 @@ static void __init free_on_init_error(void)
#endif
}
/* SB IOAPIC is always on this device in AMD systems */
#define IOAPIC_SB_DEVID ((0x00 << 8) | PCI_DEVFN(0x14, 0))
static bool __init check_ioapic_information(void)
{
bool ret, has_sb_ioapic;
int idx;
for (idx = 0; idx < nr_ioapics; idx++) {
int id = mpc_ioapic_id(idx);
has_sb_ioapic = false;
ret = false;
if (get_ioapic_devid(id) < 0) {
pr_err(FW_BUG "AMD-Vi: IO-APIC[%d] not in IVRS table\n", id);
pr_err("AMD-Vi: Disabling interrupt remapping due to BIOS Bug\n");
return false;
for (idx = 0; idx < nr_ioapics; idx++) {
int devid, id = mpc_ioapic_id(idx);
devid = get_ioapic_devid(id);
if (devid < 0) {
pr_err(FW_BUG "AMD-Vi: IOAPIC[%d] not in IVRS table\n", id);
ret = false;
} else if (devid == IOAPIC_SB_DEVID) {
has_sb_ioapic = true;
ret = true;
}
}
return true;
if (!has_sb_ioapic) {
/*
* We expect the SB IOAPIC to be listed in the IVRS
* table. The system timer is connected to the SB IOAPIC
* and if we don't have it in the list the system will
* panic at boot time. This situation usually happens
* when the BIOS is buggy and provides us the wrong
* device id for the IOAPIC in the system.
*/
pr_err(FW_BUG "AMD-Vi: No southbridge IOAPIC found in IVRS table\n");
}
if (!ret)
pr_err("AMD-Vi: Disabling interrupt remapping due to BIOS Bug(s)\n");
return ret;
}
static void __init free_dma_resources(void)