The following commit has been merged into the irq/urgent branch of tip:

Commit-ID: 71c8e2a7c822ee557b07d9bb49028dd269c87b2e Gitweb: https://git.kernel.org/tip/71c8e2a7c822ee557b07d9bb49028dd269c87b2e Author: Mark Rutland mark.rutland@arm.com AuthorDate: Thu, 22 Aug 2024 11:23:08 +01:00 Committer: Thomas Gleixner tglx@linutronix.de CommitterDate: Fri, 23 Aug 2024 12:45:45 +02:00

irqchip/gic-v3: Init SRE before poking sysregs

The GICv3 driver pokes GICv3 system registers in gic_prio_init() before gic_cpu_sys_reg_init() ensures that GICv3 system registers have been enabled by writing to ICC_SRE_EL1.SRE.

On arm64 this is benign as has_useable_gicv3_cpuif() runs earlier during cpufeature detection, and this enables the GICv3 system registers.

On 32-bit arm when booting on an FVP using the boot-wrapper, the accesses in gic_prio_init() end up being UNDEFINED and crashes the kernel during boot.

This is a regression introduced by the addition of gic_prio_init().

Fix this by factoring out the SRE initialization into a new function and calling it early in the three paths where SRE may not have been initialized:

(1) gic_init_bases(), before the primary CPU pokes GICv3 sysregs in gic_prio_init().

(2) gic_starting_cpu(), before secondary CPUs initialize GICv3 sysregs in gic_cpu_init().

(3) gic_cpu_pm_notifier(), before CPUs re-initialize GICv3 sysregs in gic_cpu_sys_reg_init().

Fixes: d447bf09a4013541 ("irqchip/gic-v3: Detect GICD_CTRL.DS and SCR_EL3.FIQ earlier") Signed-off-by: Mark Rutland mark.rutland@arm.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Reviewed-by: Marc Zyngier maz@kernel.org Cc: stable@vger.kernel.org --- drivers/irqchip/irq-gic-v3.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c index c19083b..74f21e0 100644 --- a/drivers/irqchip/irq-gic-v3.c +++ b/drivers/irqchip/irq-gic-v3.c @@ -1154,14 +1154,8 @@ static void gic_update_rdist_properties(void) gic_data.rdists.has_vpend_valid_dirty ? "Valid+Dirty " : ""); }

-static void gic_cpu_sys_reg_init(void) +static void gic_cpu_sys_reg_enable(void) { - int i, cpu = smp_processor_id(); - u64 mpidr = gic_cpu_to_affinity(cpu); - u64 need_rss = MPIDR_RS(mpidr); - bool group0; - u32 pribits; - /* * Need to check that the SRE bit has actually been set. If * not, it means that SRE is disabled at EL2. We're going to @@ -1172,6 +1166,16 @@ static void gic_cpu_sys_reg_init(void) if (!gic_enable_sre()) pr_err("GIC: unable to set SRE (disabled at EL2), panic ahead\n");

+} + +static void gic_cpu_sys_reg_init(void) +{ + int i, cpu = smp_processor_id(); + u64 mpidr = gic_cpu_to_affinity(cpu); + u64 need_rss = MPIDR_RS(mpidr); + bool group0; + u32 pribits; + pribits = gic_get_pribits();

group0 = gic_has_group0(); @@ -1333,6 +1337,7 @@ static int gic_check_rdist(unsigned int cpu)

static int gic_starting_cpu(unsigned int cpu) { + gic_cpu_sys_reg_enable(); gic_cpu_init();

if (gic_dist_supports_lpis()) @@ -1498,6 +1503,7 @@ static int gic_cpu_pm_notifier(struct notifier_block *self, if (cmd == CPU_PM_EXIT) { if (gic_dist_security_disabled()) gic_enable_redist(true); + gic_cpu_sys_reg_enable(); gic_cpu_sys_reg_init(); } else if (cmd == CPU_PM_ENTER && gic_dist_security_disabled()) { gic_write_grpen1(0); @@ -2070,6 +2076,7 @@ static int __init gic_init_bases(phys_addr_t dist_phys_base,

gic_update_rdist_properties();

+ gic_cpu_sys_reg_enable(); gic_prio_init(); gic_dist_init(); gic_cpu_init();