From 2bd3a997befc226ab4b504f05c5cbba305f3e0e6 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Tue, 2 Mar 2010 23:53:19 -0800 Subject: init: Open /dev/console from rootfs To avoid potential problems with an empty /dev open /dev/console from rootfs instead of waiting to mount our root filesystem and mounting it there. This effectively guarantees that there will be a device node, and it won't be on a filesystem that we will ever unmount, so there are no issues with leaving /dev/console open and pinning the filesystem. This is actually more effective than automatically mounting devtmpfs on /dev because it removes removes the occasionally problematic assumption that /dev/console exists from the boot code. With this patch I was able to throw busybox on my /boot partition (which has no /dev directory) and boot into userspace without problems. The only possible negative consequence I can think of is that someone out there deliberately used did not use a character device that is major 5 minor 2 for /dev/console. Does anyone know of a situation in which that could make sense? Signed-off-by: Eric W. Biederman Signed-off-by: Al Viro --- init/main.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'init/main.c') diff --git a/init/main.c b/init/main.c index 4cb47a159f02..106e02d7ffa5 100644 --- a/init/main.c +++ b/init/main.c @@ -806,11 +806,6 @@ static noinline int init_post(void) system_state = SYSTEM_RUNNING; numa_default_policy(); - if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0) - printk(KERN_WARNING "Warning: unable to open an initial console.\n"); - - (void) sys_dup(0); - (void) sys_dup(0); current->signal->flags |= SIGNAL_UNKILLABLE; @@ -873,6 +868,12 @@ static int __init kernel_init(void * unused) do_basic_setup(); + /* Open the /dev/console on the rootfs, this should never fail */ + if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0) + printk(KERN_WARNING "Warning: unable to open an initial console.\n"); + + (void) sys_dup(0); + (void) sys_dup(0); /* * check if there is an early userspace init. If yes, let it do all * the work -- cgit v1.2.3 From 452aa6999e6703ffbddd7f6ea124d3968915f3e3 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 5 Mar 2010 13:42:13 -0800 Subject: mm/pm: force GFP_NOIO during suspend/hibernation and resume There are quite a few GFP_KERNEL memory allocations made during suspend/hibernation and resume that may cause the system to hang, because the I/O operations they depend on cannot be completed due to the underlying devices being suspended. Avoid this problem by clearing the __GFP_IO and __GFP_FS bits in gfp_allowed_mask before suspend/hibernation and restoring the original values of these bits in gfp_allowed_mask durig the subsequent resume. [akpm@linux-foundation.org: fix CONFIG_PM=n linkage] Signed-off-by: Rafael J. Wysocki Reported-by: Maxim Levitsky Cc: Sebastian Ott Cc: Benjamin Herrenschmidt Cc: KOSAKI Motohiro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- init/main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'init/main.c') diff --git a/init/main.c b/init/main.c index 40aaa020cd68..41d0f10dbbc7 100644 --- a/init/main.c +++ b/init/main.c @@ -618,7 +618,7 @@ asmlinkage void __init start_kernel(void) local_irq_enable(); /* Interrupts are enabled now so all GFP allocations are safe. */ - set_gfp_allowed_mask(__GFP_BITS_MASK); + gfp_allowed_mask = __GFP_BITS_MASK; kmem_cache_init_late(); -- cgit v1.2.3 From 9a85b8d6049cbb0e7961df2069322fbc4192026a Mon Sep 17 00:00:00 2001 From: Andreas Mohr Date: Fri, 5 Mar 2010 13:42:39 -0800 Subject: init/main.c: improve usability in case of init binary failure - new Documentation/init.txt file describing various forms of failure trying to load the init binary after kernel bootup - extend the init/main.c init failure message to direct to Documentation/init.txt Signed-off-by: Andreas Mohr Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- init/main.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'init/main.c') diff --git a/init/main.c b/init/main.c index 41d0f10dbbc7..b09a828f38b5 100644 --- a/init/main.c +++ b/init/main.c @@ -847,7 +847,8 @@ static noinline int init_post(void) run_init_process("/bin/init"); run_init_process("/bin/sh"); - panic("No init found. Try passing init= option to kernel."); + panic("No init found. Try passing init= option to kernel. " + "See Linux Documentation/init.txt for guidance."); } static int __init kernel_init(void * unused) -- cgit v1.2.3 From 7463e633c5f94792dcff1afefb0d2961318a9d09 Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Fri, 5 Mar 2010 13:42:46 -0800 Subject: init/main.c: make setup_max_cpus static for !SMP The only in tree external users of the symbol setup_max_cpus are in arch/x86/. The files ./kernel/alternative.c, ./kernel/visws_quirks.c, and ./mm/kmemcheck/kmemcheck.c are all guarded by CONFIG_SMP being defined. For this case the symbol is an unsigned int and declared as an extern in include/linux/smp.h. When CONFIG_SMP is not defined the symbol setup_max_cpus is a constant value that is only used in init/main.c. Make the symbol static for this case. Signed-off-by: H Hartley Sweeten Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- init/main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'init/main.c') diff --git a/init/main.c b/init/main.c index b09a828f38b5..a1ab78ceb4b6 100644 --- a/init/main.c +++ b/init/main.c @@ -174,7 +174,7 @@ static int __init maxcpus(char *str) early_param("maxcpus", maxcpus); #else -const unsigned int setup_max_cpus = NR_CPUS; +static const unsigned int setup_max_cpus = NR_CPUS; #endif /* -- cgit v1.2.3 From 5ab116c9349ef52d6fbd2e2917a53f13194b048e Mon Sep 17 00:00:00 2001 From: Miao Xie Date: Tue, 23 Mar 2010 13:35:34 -0700 Subject: cpuset: fix the problem that cpuset_mem_spread_node() returns an offline node cpuset_mem_spread_node() returns an offline node, and causes an oops. This patch fixes it by initializing task->mems_allowed to node_states[N_HIGH_MEMORY], and updating task->mems_allowed when doing memory hotplug. Signed-off-by: Miao Xie Acked-by: David Rientjes Reported-by: Nick Piggin Tested-by: Nick Piggin Cc: Paul Menage Cc: Li Zefan Cc: Ingo Molnar Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- init/main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'init/main.c') diff --git a/init/main.c b/init/main.c index a1ab78ceb4b6..cbead27caefc 100644 --- a/init/main.c +++ b/init/main.c @@ -858,7 +858,7 @@ static int __init kernel_init(void * unused) /* * init can allocate pages on any node */ - set_mems_allowed(node_possible_map); + set_mems_allowed(node_states[N_HIGH_MEMORY]); /* * init can run on any cpu. */ -- cgit v1.2.3