From: Marc Zyngier <maz@xxxxxxxxxx> commit 0df6664531a12cdd8fc873f0cac0dcb40243d3e9 upstream. It turns out that our polling of RWP is totally wrong when checking for it in the redistributors, as we test the *distributor* bit index, whereas it is a different bit number in the RDs... Oopsie boo. This is embarassing. Not only because it is wrong, but also because it took *8 years* to notice the blunder... Just fix the damn thing. Fixes: 021f653791ad ("irqchip: gic-v3: Initial support for GICv3") Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Reviewed-by: Andre Przywara <andre.przywara@xxxxxxx> Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> Link: https://lore.kernel.org/r/20220315165034.794482-2-maz@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/irqchip/irq-gic-v3.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/drivers/irqchip/irq-gic-v3.c +++ b/drivers/irqchip/irq-gic-v3.c @@ -92,11 +92,11 @@ static inline void __iomem *gic_dist_bas return NULL; } -static void gic_do_wait_for_rwp(void __iomem *base) +static void gic_do_wait_for_rwp(void __iomem *base, u32 bit) { u32 count = 1000000; /* 1s! */ - while (readl_relaxed(base + GICD_CTLR) & GICD_CTLR_RWP) { + while (readl_relaxed(base + GICD_CTLR) & bit) { count--; if (!count) { pr_err_ratelimited("RWP timeout, gone fishing\n"); @@ -110,13 +110,13 @@ static void gic_do_wait_for_rwp(void __i /* Wait for completion of a distributor change */ static void gic_dist_wait_for_rwp(void) { - gic_do_wait_for_rwp(gic_data.dist_base); + gic_do_wait_for_rwp(gic_data.dist_base, GICD_CTLR_RWP); } /* Wait for completion of a redistributor change */ static void gic_redist_wait_for_rwp(void) { - gic_do_wait_for_rwp(gic_data_rdist_rd_base()); + gic_do_wait_for_rwp(gic_data_rdist_rd_base(), GICR_CTLR_RWP); } #ifdef CONFIG_ARM64 Patches currently in stable-queue which might be from maz@xxxxxxxxxx are queue-4.9/irqchip-gic-v3-fix-gicr_ctlr.rwp-polling.patch queue-4.9/irqchip-nvic-release-nvic_base-upon-failure.patch