On Wed, 29 May 2024 14:34:40 +0100 Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> wrote: > From: James Morse <james.morse@xxxxxxx> > > gic_acpi_match_gicc() is only called via gic_acpi_count_gicr_regions(). > It should only count the number of enabled redistributors, but it > also tries to sanity check the GICC entry, currently returning an > error if the Enabled bit is set, but the gicr_base_address is zero. > > Adding support for the online-capable bit to the sanity check will > complicate it, for no benefit. The existing check implicitly depends on > gic_acpi_count_gicr_regions() previous failing to find any GICR regions > (as it is valid to have gicr_base_address of zero if the redistributors > are described via a GICR entry). > > Instead of complicating the check, remove it. Failures that happen at > this point cause the irqchip not to register, meaning no irqs can be > requested. The kernel grinds to a panic() pretty quickly. > > Without the check, MADT tables that exhibit this problem are still > caught by gic_populate_rdist(), which helpfully also prints what went > wrong: > | CPU4: mpidr 100 has no re-distributor! > > Signed-off-by: James Morse <james.morse@xxxxxxx> > Reviewed-by: Gavin Shan <gshan@xxxxxxxxxx> > Tested-by: Miguel Luis <miguel.luis@xxxxxxxxxx> > Signed-off-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx> > Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> > Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> Sorry. I managed not to pick up Marc's RB form v8 and this patch is unchanged. https://lore.kernel.org/all/87jzkktaui.wl-maz@xxxxxxxxxx/ Hopefully whoever picks this up is using tooling (b4 or similar) that will get it from here. Reviewed-by: Marc Zyngier <maz@xxxxxxxxxx> So just patch 14 waiting for Marc to take another glance. > --- > drivers/irqchip/irq-gic-v3.c | 13 ++----------- > 1 file changed, 2 insertions(+), 11 deletions(-) > > diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c > index 6fb276504bcc..10af15f93d4d 100644 > --- a/drivers/irqchip/irq-gic-v3.c > +++ b/drivers/irqchip/irq-gic-v3.c > @@ -2415,19 +2415,10 @@ static int __init gic_acpi_match_gicc(union acpi_subtable_headers *header, > * If GICC is enabled and has valid gicr base address, then it means > * GICR base is presented via GICC > */ > - if (acpi_gicc_is_usable(gicc) && gicc->gicr_base_address) { > + if (acpi_gicc_is_usable(gicc) && gicc->gicr_base_address) > acpi_data.enabled_rdists++; > - return 0; > - } > > - /* > - * It's perfectly valid firmware can pass disabled GICC entry, driver > - * should not treat as errors, skip the entry instead of probe fail. > - */ > - if (!acpi_gicc_is_usable(gicc)) > - return 0; > - > - return -ENODEV; > + return 0; > } > > static int __init gic_acpi_count_gicr_regions(void)
