From f776c5ec4690b21b3668ad5956774a22c86f541a Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Mon, 18 Jan 2010 14:36:12 +0100 Subject: [PATCH 1/2] driver-core: fix devtmpfs crash on s390 On Mon, Jan 18, 2010 at 05:26:20PM +0530, Sachin Sant wrote: > Hello Heiko, > > Today while trying to boot next-20100118 i came across > the following Oops : > > Brought up 4 CPUs > Unable to handle kernel pointer dereference at virtual kernel address 0000000000 > 543000 > Oops: 0004 #1 SMP > Modules linked in: > CPU: 0 Not tainted 2.6.33-rc4-autotest-next-20100118-5-default #1 > Process swapper (pid: 1, task: 00000000fd792038, ksp: 00000000fd797a30) > Krnl PSW : 0704200180000000 00000000001eb0b8 (shmem_parse_options+0xc0/0x328) > R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:2 PM:0 EA:3 > Krnl GPRS: 000000000054388a 000000000000003d 0000000000543836 000000000000003d > 0000000000000000 0000000000483f28 0000000000536112 00000000fd797d00 > 00000000fd4ba100 0000000000000100 0000000000483978 0000000000543832 > 0000000000000000 0000000000465958 00000000001eb0b0 00000000fd797c58 > Krnl Code: 00000000001eb0aa: c0e5000994f1 brasl %r14,31da8c > 00000000001eb0b0: b9020022 ltgr %r2,%r2 > 00000000001eb0b4: a784010b brc 8,1eb2ca > >00000000001eb0b8: 92002000 mvi 0(%r2),0 > 00000000001eb0bc: a7080000 lhi %r0,0 > 00000000001eb0c0: 41902001 la %r9,1(%r2) > 00000000001eb0c4: b9040016 lgr %r1,%r6 > 00000000001eb0c8: b904002b lgr %r2,%r11 > Call Trace: > (<00000000fd797c50> 0xfd797c50) > <00000000001eb5da> shmem_fill_super+0x13a/0x25c > <0000000000228cfa> get_sb_single+0xbe/0xdc > <000000000034ffc0> dev_get_sb+0x2c/0x38 > <000000000066c602> devtmpfs_init+0x46/0xc0 > <000000000066c53e> driver_init+0x22/0x60 > <000000000064d40a> kernel_init+0x24e/0x3d0 > <000000000010a7ea> kernel_thread_starter+0x6/0xc > <000000000010a7e4> kernel_thread_starter+0x0/0xc > > I never tried to boot a kernel with DEVTMPFS enabled on a s390 box. > So am wondering if this is supported or not ? If you think this > is supported i will send a mail to community on this. There is nothing arch specific to devtmpfs. This part crashes because the kernel tries to modify the data read-only section which is write protected on s390. Signed-off-by: Heiko Carstens Acked-by: Kay Sievers Signed-off-by: Greg Kroah-Hartman --- drivers/base/devtmpfs.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/base/devtmpfs.c b/drivers/base/devtmpfs.c index 090dd4851301..42ae452b36b0 100644 --- a/drivers/base/devtmpfs.c +++ b/drivers/base/devtmpfs.c @@ -354,6 +354,7 @@ int __init devtmpfs_init(void) { int err; struct vfsmount *mnt; + char options[] = "mode=0755"; err = register_filesystem(&dev_fs_type); if (err) { @@ -362,7 +363,7 @@ int __init devtmpfs_init(void) return err; } - mnt = kern_mount_data(&dev_fs_type, "mode=0755"); + mnt = kern_mount_data(&dev_fs_type, options); if (IS_ERR(mnt)) { err = PTR_ERR(mnt); printk(KERN_ERR "devtmpfs: unable to create devtmpfs %i\n", err); From bd796671f093d5b1841d383674d5650f5ec6c9c6 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Tue, 19 Jan 2010 13:08:16 -0800 Subject: [PATCH 2/2] Revert "sysdev: fix prototype for memory_sysdev_class show/store functions" This reverts commit 8ff410daa009c4b44be445ded5b0cec00abc0426 It should not have been sent to Linus's tree yet, as it depends on changes that are queued up in my driver-core for the .34 kernel merge. Cc: Wu Fengguang Cc: Andi Kleen Cc: "Zheng, Shaohui" Cc: Andrew Morton Cc: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- drivers/base/memory.c | 32 ++++++++++++-------------------- 1 file changed, 12 insertions(+), 20 deletions(-) diff --git a/drivers/base/memory.c b/drivers/base/memory.c index ae6b6c43cff9..bd025059711f 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -309,19 +309,17 @@ static SYSDEV_ATTR(removable, 0444, show_mem_removable, NULL); * Block size attribute stuff */ static ssize_t -print_block_size(struct sysdev_class *class, - struct sysdev_class_attribute *class_attr, - char *buf) +print_block_size(struct class *class, char *buf) { return sprintf(buf, "%#lx\n", (unsigned long)PAGES_PER_SECTION * PAGE_SIZE); } -static SYSDEV_CLASS_ATTR(block_size_bytes, 0444, print_block_size, NULL); +static CLASS_ATTR(block_size_bytes, 0444, print_block_size, NULL); static int block_size_init(void) { return sysfs_create_file(&memory_sysdev_class.kset.kobj, - &attr_block_size_bytes.attr); + &class_attr_block_size_bytes.attr); } /* @@ -332,9 +330,7 @@ static int block_size_init(void) */ #ifdef CONFIG_ARCH_MEMORY_PROBE static ssize_t -memory_probe_store(struct sysdev_class *class, - struct sysdev_class_attribute *class_attr, - const char *buf, size_t count) +memory_probe_store(struct class *class, const char *buf, size_t count) { u64 phys_addr; int nid; @@ -350,12 +346,12 @@ memory_probe_store(struct sysdev_class *class, return count; } -static SYSDEV_CLASS_ATTR(probe, S_IWUSR, NULL, memory_probe_store); +static CLASS_ATTR(probe, S_IWUSR, NULL, memory_probe_store); static int memory_probe_init(void) { return sysfs_create_file(&memory_sysdev_class.kset.kobj, - &attr_probe.attr); + &class_attr_probe.attr); } #else static inline int memory_probe_init(void) @@ -371,9 +367,7 @@ static inline int memory_probe_init(void) /* Soft offline a page */ static ssize_t -store_soft_offline_page(struct sysdev_class *class, - struct sysdev_class_attribute *class_attr, - const char *buf, size_t count) +store_soft_offline_page(struct class *class, const char *buf, size_t count) { int ret; u64 pfn; @@ -390,9 +384,7 @@ store_soft_offline_page(struct sysdev_class *class, /* Forcibly offline a page, including killing processes. */ static ssize_t -store_hard_offline_page(struct sysdev_class *class, - struct sysdev_class_attribute *class_attr, - const char *buf, size_t count) +store_hard_offline_page(struct class *class, const char *buf, size_t count) { int ret; u64 pfn; @@ -405,18 +397,18 @@ store_hard_offline_page(struct sysdev_class *class, return ret ? ret : count; } -static SYSDEV_CLASS_ATTR(soft_offline_page, 0644, NULL, store_soft_offline_page); -static SYSDEV_CLASS_ATTR(hard_offline_page, 0644, NULL, store_hard_offline_page); +static CLASS_ATTR(soft_offline_page, 0644, NULL, store_soft_offline_page); +static CLASS_ATTR(hard_offline_page, 0644, NULL, store_hard_offline_page); static __init int memory_fail_init(void) { int err; err = sysfs_create_file(&memory_sysdev_class.kset.kobj, - &attr_soft_offline_page.attr); + &class_attr_soft_offline_page.attr); if (!err) err = sysfs_create_file(&memory_sysdev_class.kset.kobj, - &attr_hard_offline_page.attr); + &class_attr_hard_offline_page.attr); return err; } #else