From 88d84ac97378c2f1d5fec9af1e8b7d9a662d6b00 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Fri, 19 Jul 2013 12:28:25 +0200 Subject: [PATCH] EDAC: Fix lockdep splat Fix the following: BUG: key ffff88043bdd0330 not in .data! ------------[ cut here ]------------ WARNING: at kernel/lockdep.c:2987 lockdep_init_map+0x565/0x5a0() DEBUG_LOCKS_WARN_ON(1) Modules linked in: glue_helper sb_edac(+) edac_core snd acpi_cpufreq lrw gf128mul ablk_helper iTCO_wdt evdev i2c_i801 dcdbas button cryptd pcspkr iTCO_vendor_support usb_common lpc_ich mfd_core soundcore mperf processor microcode CPU: 2 PID: 599 Comm: modprobe Not tainted 3.10.0 #1 Hardware name: Dell Inc. Precision T3600/0PTTT9, BIOS A08 01/24/2013 0000000000000009 ffff880439a1d920 ffffffff8160a9a9 ffff880439a1d958 ffffffff8103d9e0 ffff88043af4a510 ffffffff81a16e11 0000000000000000 ffff88043bdd0330 0000000000000000 ffff880439a1d9b8 ffffffff8103dacc Call Trace: dump_stack warn_slowpath_common warn_slowpath_fmt lockdep_init_map ? trace_hardirqs_on_caller ? trace_hardirqs_on debug_mutex_init __mutex_init bus_register edac_create_sysfs_mci_device edac_mc_add_mc sbridge_probe pci_device_probe driver_probe_device __driver_attach ? driver_probe_device bus_for_each_dev driver_attach bus_add_driver driver_register __pci_register_driver ? 0xffffffffa0010fff sbridge_init ? 0xffffffffa0010fff do_one_initcall load_module ? unset_module_init_ro_nx SyS_init_module tracesys ---[ end trace d24a70b0d3ddf733 ]--- EDAC MC0: Giving out device to 'sbridge_edac.c' 'Sandy Bridge Socket#0': DEV 0000:3f:0e.0 EDAC sbridge: Driver loaded. What happens is that bus_register needs a statically allocated lock_key because the last is handed in to lockdep. However, struct mem_ctl_info embeds struct bus_type (the whole struct, not a pointer to it) and the whole thing gets dynamically allocated. Fix this by using a statically allocated struct bus_type for the MC bus. Signed-off-by: Borislav Petkov Acked-by: Mauro Carvalho Chehab Cc: Markus Trippelsdorf Cc: stable@kernel.org # v3.10 Signed-off-by: Tony Luck --- drivers/edac/edac_mc.c | 9 +++++++++ drivers/edac/edac_mc_sysfs.c | 28 +++++++++++++++------------- drivers/edac/i5100_edac.c | 2 +- include/linux/edac.h | 7 ++++++- 4 files changed, 31 insertions(+), 15 deletions(-) diff --git a/drivers/edac/edac_mc.c b/drivers/edac/edac_mc.c index 27e86d9..89e1090 100644 --- a/drivers/edac/edac_mc.c +++ b/drivers/edac/edac_mc.c @@ -48,6 +48,8 @@ static LIST_HEAD(mc_devices); */ static void const *edac_mc_owner; +static struct bus_type mc_bus[EDAC_MAX_MCS]; + unsigned edac_dimm_info_location(struct dimm_info *dimm, char *buf, unsigned len) { @@ -723,6 +725,11 @@ int edac_mc_add_mc(struct mem_ctl_info *mci) int ret = -EINVAL; edac_dbg(0, "\n"); + if (mci->mc_idx >= EDAC_MAX_MCS) { + pr_warn_once("Too many memory controllers: %d\n", mci->mc_idx); + return -ENODEV; + } + #ifdef CONFIG_EDAC_DEBUG if (edac_debug_level >= 3) edac_mc_dump_mci(mci); @@ -762,6 +769,8 @@ int edac_mc_add_mc(struct mem_ctl_info *mci) /* set load time so that error rate can be tracked */ mci->start_time = jiffies; + mci->bus = &mc_bus[mci->mc_idx]; + if (edac_create_sysfs_mci_device(mci)) { edac_mc_printk(mci, KERN_WARNING, "failed to create sysfs device\n"); diff --git a/drivers/edac/edac_mc_sysfs.c b/drivers/edac/edac_mc_sysfs.c index ef15a7e..e7c32c4 100644 --- a/drivers/edac/edac_mc_sysfs.c +++ b/drivers/edac/edac_mc_sysfs.c @@ -370,7 +370,7 @@ static int edac_create_csrow_object(struct mem_ctl_info *mci, return -ENODEV; csrow->dev.type = &csrow_attr_type; - csrow->dev.bus = &mci->bus; + csrow->dev.bus = mci->bus; device_initialize(&csrow->dev); csrow->dev.parent = &mci->dev; csrow->mci = mci; @@ -605,7 +605,7 @@ static int edac_create_dimm_object(struct mem_ctl_info *mci, dimm->mci = mci; dimm->dev.type = &dimm_attr_type; - dimm->dev.bus = &mci->bus; + dimm->dev.bus = mci->bus; device_initialize(&dimm->dev); dimm->dev.parent = &mci->dev; @@ -975,11 +975,13 @@ int edac_create_sysfs_mci_device(struct mem_ctl_info *mci) * The memory controller needs its own bus, in order to avoid * namespace conflicts at /sys/bus/edac. */ - mci->bus.name = kasprintf(GFP_KERNEL, "mc%d", mci->mc_idx); - if (!mci->bus.name) + mci->bus->name = kasprintf(GFP_KERNEL, "mc%d", mci->mc_idx); + if (!mci->bus->name) return -ENOMEM; - edac_dbg(0, "creating bus %s\n", mci->bus.name); - err = bus_register(&mci->bus); + + edac_dbg(0, "creating bus %s\n", mci->bus->name); + + err = bus_register(mci->bus); if (err < 0) return err; @@ -988,7 +990,7 @@ int edac_create_sysfs_mci_device(struct mem_ctl_info *mci) device_initialize(&mci->dev); mci->dev.parent = mci_pdev; - mci->dev.bus = &mci->bus; + mci->dev.bus = mci->bus; dev_set_name(&mci->dev, "mc%d", mci->mc_idx); dev_set_drvdata(&mci->dev, mci); pm_runtime_forbid(&mci->dev); @@ -997,8 +999,8 @@ int edac_create_sysfs_mci_device(struct mem_ctl_info *mci) err = device_add(&mci->dev); if (err < 0) { edac_dbg(1, "failure: create device %s\n", dev_name(&mci->dev)); - bus_unregister(&mci->bus); - kfree(mci->bus.name); + bus_unregister(mci->bus); + kfree(mci->bus->name); return err; } @@ -1064,8 +1066,8 @@ fail: } fail2: device_unregister(&mci->dev); - bus_unregister(&mci->bus); - kfree(mci->bus.name); + bus_unregister(mci->bus); + kfree(mci->bus->name); return err; } @@ -1098,8 +1100,8 @@ void edac_unregister_sysfs(struct mem_ctl_info *mci) { edac_dbg(1, "Unregistering device %s\n", dev_name(&mci->dev)); device_unregister(&mci->dev); - bus_unregister(&mci->bus); - kfree(mci->bus.name); + bus_unregister(mci->bus); + kfree(mci->bus->name); } static void mc_attr_release(struct device *dev) diff --git a/drivers/edac/i5100_edac.c b/drivers/edac/i5100_edac.c index 1b63517..157b934 100644 --- a/drivers/edac/i5100_edac.c +++ b/drivers/edac/i5100_edac.c @@ -974,7 +974,7 @@ static int i5100_setup_debugfs(struct mem_ctl_info *mci) if (!i5100_debugfs) return -ENODEV; - priv->debugfs = debugfs_create_dir(mci->bus.name, i5100_debugfs); + priv->debugfs = debugfs_create_dir(mci->bus->name, i5100_debugfs); if (!priv->debugfs) return -ENOMEM; diff --git a/include/linux/edac.h b/include/linux/edac.h index 0b76327..5c6d7fb 100644 --- a/include/linux/edac.h +++ b/include/linux/edac.h @@ -622,7 +622,7 @@ struct edac_raw_error_desc { */ struct mem_ctl_info { struct device dev; - struct bus_type bus; + struct bus_type *bus; struct list_head link; /* for global list of mem_ctl_info structs */ @@ -742,4 +742,9 @@ struct mem_ctl_info { #endif }; +/* + * Maximum number of memory controllers in the coherent fabric. + */ +#define EDAC_MAX_MCS 16 + #endif -- 2.7.4