From 9f85550347f51c79a917b2aec04c90691c11e20a Mon Sep 17 00:00:00 2001 From: Linus Walleij Date: Tue, 10 Apr 2012 12:37:42 +0100 Subject: ARM: 7359/2: smp_twd: Only wait for reprogramming on active cpus During booting of cpu1, there is a short window where cpu1 is online, but not active where cpu1 is occupied by waiting to become active. If cpu0 then decides to schedule something on cpu1 and wait for it to complete, before cpu0 has set cpu1 active, we have a deadlock. Typically it's this CPU frequency transition that happens at this time, so let's just not wait for it to happen, it will happen whenever the CPU eventually comes online instead. Cc: Peter Zijlstra Cc: stable@kernel.org Signed-off-by: Jonas Aaberg Reviewed-by: Rickard Andersson Signed-off-by: Linus Walleij Signed-off-by: Russell King --- arch/arm/kernel/smp_twd.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'arch/arm/kernel') diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c index fef42b21cecb..5b150afb995b 100644 --- a/arch/arm/kernel/smp_twd.c +++ b/arch/arm/kernel/smp_twd.c @@ -118,10 +118,14 @@ static int twd_cpufreq_transition(struct notifier_block *nb, * The twd clock events must be reprogrammed to account for the new * frequency. The timer is local to a cpu, so cross-call to the * changing cpu. + * + * Only wait for it to finish, if the cpu is active to avoid + * deadlock when cpu1 is spinning on while(!cpu_active(cpu1)) during + * booting of that cpu. */ if (state == CPUFREQ_POSTCHANGE || state == CPUFREQ_RESUMECHANGE) smp_call_function_single(freqs->cpu, twd_update_frequency, - NULL, 1); + NULL, cpu_active(freqs->cpu)); return NOTIFY_OK; } -- cgit v1.2.2 From e5ab85800820edd907d3f43f285e1232f84d5a41 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Thu, 12 Apr 2012 17:15:08 +0100 Subject: ARM: 7382/1: mm: truncate memory banks to fit in 4GB space for classic MMU If a bank of memory spanning the 4GB boundary is added on a !CONFIG_LPAE kernel then we will hang early during boot since the memory bank will have wrapped around to zero. This patch truncates memory banks for !LPAE configurations when the end address is not representable in 32 bits. Acked-by: Nicolas Pitre Signed-off-by: Will Deacon Signed-off-by: Russell King --- arch/arm/kernel/setup.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) (limited to 'arch/arm/kernel') diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index b91411371ae1..ebfac782593f 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -523,7 +523,21 @@ int __init arm_add_memory(phys_addr_t start, unsigned long size) */ size -= start & ~PAGE_MASK; bank->start = PAGE_ALIGN(start); - bank->size = size & PAGE_MASK; + +#ifndef CONFIG_LPAE + if (bank->start + size < bank->start) { + printk(KERN_CRIT "Truncating memory at 0x%08llx to fit in " + "32-bit physical address space\n", (long long)start); + /* + * To ensure bank->start + bank->size is representable in + * 32 bits, we use ULONG_MAX as the upper limit rather than 4GB. + * This means we lose a page after masking. + */ + size = ULONG_MAX - bank->start; + } +#endif + + bank->size = size & PAGE_MASK; /* * Check whether this memory region has non-zero size or -- cgit v1.2.2