| Message ID | 20200916172228.83271-3-ganeshgr@linux.ibm.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | powerpc/mce: Fix mce handler and add selftest | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | success | Successfully applied on branch powerpc/merge (27e2fbcd815a088d7d83c7158f76b6e95ab07c50) |
| snowpatch_ozlabs/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 165 lines checked |
| snowpatch_ozlabs/needsstable | success | Patch has no Fixes tags |
Hi Ganesh,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on powerpc/next]
[also build test ERROR on v5.9-rc5 next-20200916]
[cannot apply to scottwood/next mpe/next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Ganesh-Goudar/powerpc-mce-Fix-mce-handler-and-add-selftest/20200917-092355
base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc-randconfig-r021-20200917 (attached as .config)
compiler: powerpc-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=powerpc
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
arch/powerpc/sysdev/mce_error_inject.c: In function 'get_slb_index':
>> arch/powerpc/sysdev/mce_error_inject.c:17:10: error: implicit declaration of function 'get_paca' [-Werror=implicit-function-declaration]
17 | index = get_paca()->stab_rr;
| ^~~~~~~~
>> arch/powerpc/sysdev/mce_error_inject.c:17:20: error: invalid type argument of '->' (have 'int')
17 | index = get_paca()->stab_rr;
| ^~
>> arch/powerpc/sysdev/mce_error_inject.c:22:15: error: 'mmu_slb_size' undeclared (first use in this function)
22 | if (index < (mmu_slb_size - 1))
| ^~~~~~~~~~~~
arch/powerpc/sysdev/mce_error_inject.c:22:15: note: each undeclared identifier is reported only once for each function it appears in
>> arch/powerpc/sysdev/mce_error_inject.c:25:11: error: 'SLB_NUM_BOLTED' undeclared (first use in this function)
25 | index = SLB_NUM_BOLTED;
| ^~~~~~~~~~~~~~
arch/powerpc/sysdev/mce_error_inject.c:26:12: error: invalid type argument of '->' (have 'int')
26 | get_paca()->stab_rr = index;
| ^~
arch/powerpc/sysdev/mce_error_inject.c: In function 'mk_esid_data':
>> arch/powerpc/sysdev/mce_error_inject.c:31:15: error: 'MMU_SEGSIZE_256M' undeclared (first use in this function); did you mean 'MMU_PAGE_256M'?
31 | (((ssize) == MMU_SEGSIZE_256M) ? ESID_MASK : ESID_MASK_1T)
| ^~~~~~~~~~~~~~~~
arch/powerpc/sysdev/mce_error_inject.c:36:15: note: in expansion of macro 'slb_esid_mask'
36 | return (ea & slb_esid_mask(ssize)) | SLB_ESID_V | slot;
| ^~~~~~~~~~~~~
>> arch/powerpc/sysdev/mce_error_inject.c:31:35: error: 'ESID_MASK' undeclared (first use in this function); did you mean 'NMI_MASK'?
31 | (((ssize) == MMU_SEGSIZE_256M) ? ESID_MASK : ESID_MASK_1T)
| ^~~~~~~~~
arch/powerpc/sysdev/mce_error_inject.c:36:15: note: in expansion of macro 'slb_esid_mask'
36 | return (ea & slb_esid_mask(ssize)) | SLB_ESID_V | slot;
| ^~~~~~~~~~~~~
>> arch/powerpc/sysdev/mce_error_inject.c:31:47: error: 'ESID_MASK_1T' undeclared (first use in this function)
31 | (((ssize) == MMU_SEGSIZE_256M) ? ESID_MASK : ESID_MASK_1T)
| ^~~~~~~~~~~~
arch/powerpc/sysdev/mce_error_inject.c:36:15: note: in expansion of macro 'slb_esid_mask'
36 | return (ea & slb_esid_mask(ssize)) | SLB_ESID_V | slot;
| ^~~~~~~~~~~~~
>> arch/powerpc/sysdev/mce_error_inject.c:36:39: error: 'SLB_ESID_V' undeclared (first use in this function)
36 | return (ea & slb_esid_mask(ssize)) | SLB_ESID_V | slot;
| ^~~~~~~~~~
arch/powerpc/sysdev/mce_error_inject.c: In function 'mk_vsid_data':
>> arch/powerpc/sysdev/mce_error_inject.c:45:10: error: implicit declaration of function 'get_kernel_vsid' [-Werror=implicit-function-declaration]
45 | return (get_kernel_vsid(ea, ssize) << slb_vsid_shift(ssize)) | flags |
| ^~~~~~~~~~~~~~~
arch/powerpc/sysdev/mce_error_inject.c:40:14: error: 'MMU_SEGSIZE_256M' undeclared (first use in this function); did you mean 'MMU_PAGE_256M'?
40 | ((ssize) == MMU_SEGSIZE_256M ? SLB_VSID_SHIFT : SLB_VSID_SHIFT_1T)
| ^~~~~~~~~~~~~~~~
arch/powerpc/sysdev/mce_error_inject.c:45:40: note: in expansion of macro 'slb_vsid_shift'
45 | return (get_kernel_vsid(ea, ssize) << slb_vsid_shift(ssize)) | flags |
| ^~~~~~~~~~~~~~
>> arch/powerpc/sysdev/mce_error_inject.c:40:33: error: 'SLB_VSID_SHIFT' undeclared (first use in this function)
40 | ((ssize) == MMU_SEGSIZE_256M ? SLB_VSID_SHIFT : SLB_VSID_SHIFT_1T)
| ^~~~~~~~~~~~~~
arch/powerpc/sysdev/mce_error_inject.c:45:40: note: in expansion of macro 'slb_vsid_shift'
45 | return (get_kernel_vsid(ea, ssize) << slb_vsid_shift(ssize)) | flags |
| ^~~~~~~~~~~~~~
>> arch/powerpc/sysdev/mce_error_inject.c:40:50: error: 'SLB_VSID_SHIFT_1T' undeclared (first use in this function)
40 | ((ssize) == MMU_SEGSIZE_256M ? SLB_VSID_SHIFT : SLB_VSID_SHIFT_1T)
| ^~~~~~~~~~~~~~~~~
arch/powerpc/sysdev/mce_error_inject.c:45:40: note: in expansion of macro 'slb_vsid_shift'
45 | return (get_kernel_vsid(ea, ssize) << slb_vsid_shift(ssize)) | flags |
| ^~~~~~~~~~~~~~
>> arch/powerpc/sysdev/mce_error_inject.c:46:28: error: 'SLB_VSID_SSIZE_SHIFT' undeclared (first use in this function)
46 | ((unsigned long)ssize << SLB_VSID_SSIZE_SHIFT);
| ^~~~~~~~~~~~~~~~~~~~
arch/powerpc/sysdev/mce_error_inject.c: In function 'insert_slb_entry':
>> arch/powerpc/sysdev/mce_error_inject.c:54:10: error: 'SLB_VSID_KERNEL' undeclared (first use in this function)
54 | flags = SLB_VSID_KERNEL | mmu_psize_defs[MMU_PAGE_64K].sllp;
| ^~~~~~~~~~~~~~~
>> arch/powerpc/sysdev/mce_error_inject.c:54:28: error: 'mmu_psize_defs' undeclared (first use in this function)
54 | flags = SLB_VSID_KERNEL | mmu_psize_defs[MMU_PAGE_64K].sllp;
| ^~~~~~~~~~~~~~
>> arch/powerpc/sysdev/mce_error_inject.c:58:7: error: assignment to 'struct paca_struct *' from 'int' makes pointer from integer without a cast [-Werror=int-conversion]
58 | paca = get_paca();
| ^
>> arch/powerpc/sysdev/mce_error_inject.c:52:22: error: variable 'paca' set but not used [-Werror=unused-but-set-variable]
52 | struct paca_struct *paca;
| ^~~~
arch/powerpc/sysdev/mce_error_inject.c: In function 'inject_vmalloc_slb_multihit':
>> arch/powerpc/sysdev/mce_error_inject.c:83:22: error: 'MMU_SEGSIZE_1T' undeclared (first use in this function)
83 | insert_slb_entry(p, MMU_SEGSIZE_1T);
| ^~~~~~~~~~~~~~
arch/powerpc/sysdev/mce_error_inject.c: In function 'inject_kmalloc_slb_multihit':
arch/powerpc/sysdev/mce_error_inject.c:95:22: error: 'MMU_SEGSIZE_1T' undeclared (first use in this function)
95 | insert_slb_entry(p, MMU_SEGSIZE_1T);
| ^~~~~~~~~~~~~~
cc1: all warnings being treated as errors
# https://github.com/0day-ci/linux/commit/4ab1196e8e542fdf0e7cda8638dfb0e5771fd98e
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Ganesh-Goudar/powerpc-mce-Fix-mce-handler-and-add-selftest/20200917-092355
git checkout 4ab1196e8e542fdf0e7cda8638dfb0e5771fd98e
vim +/get_paca +17 arch/powerpc/sysdev/mce_error_inject.c
12
13 static inline unsigned long get_slb_index(void)
14 {
15 unsigned long index;
16
> 17 index = get_paca()->stab_rr;
18
19 /*
20 * simple round-robin replacement of slb starting at SLB_NUM_BOLTED.
21 */
> 22 if (index < (mmu_slb_size - 1))
23 index++;
24 else
> 25 index = SLB_NUM_BOLTED;
26 get_paca()->stab_rr = index;
27 return index;
28 }
29
30 #define slb_esid_mask(ssize) \
> 31 (((ssize) == MMU_SEGSIZE_256M) ? ESID_MASK : ESID_MASK_1T)
32
33 static inline unsigned long mk_esid_data(unsigned long ea, int ssize,
34 unsigned long slot)
35 {
> 36 return (ea & slb_esid_mask(ssize)) | SLB_ESID_V | slot;
37 }
38
39 #define slb_vsid_shift(ssize) \
> 40 ((ssize) == MMU_SEGSIZE_256M ? SLB_VSID_SHIFT : SLB_VSID_SHIFT_1T)
41
42 static inline unsigned long mk_vsid_data(unsigned long ea, int ssize,
43 unsigned long flags)
44 {
> 45 return (get_kernel_vsid(ea, ssize) << slb_vsid_shift(ssize)) | flags |
> 46 ((unsigned long)ssize << SLB_VSID_SSIZE_SHIFT);
47 }
48
49 static void insert_slb_entry(char *p, int ssize)
50 {
51 unsigned long flags, entry;
> 52 struct paca_struct *paca;
53
> 54 flags = SLB_VSID_KERNEL | mmu_psize_defs[MMU_PAGE_64K].sllp;
55
56 preempt_disable();
57
> 58 paca = get_paca();
59
60 entry = get_slb_index();
61 asm volatile("slbmte %0,%1" :
62 : "r" (mk_vsid_data((unsigned long)p, ssize, flags)),
63 "r" (mk_esid_data((unsigned long)p, ssize, entry))
64 : "memory");
65
66 entry = get_slb_index();
67 asm volatile("slbmte %0,%1" :
68 : "r" (mk_vsid_data((unsigned long)p, ssize, flags)),
69 "r" (mk_esid_data((unsigned long)p, ssize, entry))
70 : "memory");
71 preempt_enable();
72 p[0] = '!';
73 }
74
75 static void inject_vmalloc_slb_multihit(void)
76 {
77 char *p;
78
79 p = vmalloc(2048);
80 if (!p)
81 return;
82
> 83 insert_slb_entry(p, MMU_SEGSIZE_1T);
84 vfree(p);
85 }
86
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
Hi Ganesh,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on powerpc/next]
[also build test WARNING on v5.9-rc5 next-20200916]
[cannot apply to scottwood/next mpe/next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Ganesh-Goudar/powerpc-mce-Fix-mce-handler-and-add-selftest/20200917-092355
base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc-allyesconfig (attached as .config)
compiler: powerpc64-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=powerpc
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
arch/powerpc/sysdev/mce_error_inject.c: In function 'insert_slb_entry':
>> arch/powerpc/sysdev/mce_error_inject.c:52:22: warning: variable 'paca' set but not used [-Wunused-but-set-variable]
52 | struct paca_struct *paca;
| ^~~~
# https://github.com/0day-ci/linux/commit/4ab1196e8e542fdf0e7cda8638dfb0e5771fd98e
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Ganesh-Goudar/powerpc-mce-Fix-mce-handler-and-add-selftest/20200917-092355
git checkout 4ab1196e8e542fdf0e7cda8638dfb0e5771fd98e
vim +/paca +52 arch/powerpc/sysdev/mce_error_inject.c
48
49 static void insert_slb_entry(char *p, int ssize)
50 {
51 unsigned long flags, entry;
> 52 struct paca_struct *paca;
53
54 flags = SLB_VSID_KERNEL | mmu_psize_defs[MMU_PAGE_64K].sllp;
55
56 preempt_disable();
57
58 paca = get_paca();
59
60 entry = get_slb_index();
61 asm volatile("slbmte %0,%1" :
62 : "r" (mk_vsid_data((unsigned long)p, ssize, flags)),
63 "r" (mk_esid_data((unsigned long)p, ssize, entry))
64 : "memory");
65
66 entry = get_slb_index();
67 asm volatile("slbmte %0,%1" :
68 : "r" (mk_vsid_data((unsigned long)p, ssize, flags)),
69 "r" (mk_esid_data((unsigned long)p, ssize, entry))
70 : "memory");
71 preempt_enable();
72 p[0] = '!';
73 }
74
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
Hello, On Wed, Sep 16, 2020 at 10:52:27PM +0530, Ganesh Goudar wrote: > To test machine check handling, add debugfs interface to inject > slb multihit errors. > > To inject slb multihit: > #echo 1 > /sys/kernel/debug/powerpc/mce_error_inject/inject_slb_multihit > > Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com> > Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> > --- > arch/powerpc/Kconfig.debug | 9 ++ > arch/powerpc/sysdev/Makefile | 2 + > arch/powerpc/sysdev/mce_error_inject.c | 148 +++++++++++++++++++++++++ > 3 files changed, 159 insertions(+) > create mode 100644 arch/powerpc/sysdev/mce_error_inject.c > > diff --git a/arch/powerpc/Kconfig.debug b/arch/powerpc/Kconfig.debug > index b88900f4832f..61db133f2f0d 100644 > --- a/arch/powerpc/Kconfig.debug > +++ b/arch/powerpc/Kconfig.debug > @@ -398,3 +398,12 @@ config KASAN_SHADOW_OFFSET > hex > depends on KASAN > default 0xe0000000 > + > +config MCE_ERROR_INJECT > + bool "Enable MCE error injection through debugfs" > + depends on DEBUG_FS > + default y > + help > + This option creates an mce_error_inject directory in the > + powerpc debugfs directory that allows limited injection of > + Machine Check Errors (MCEs). > diff --git a/arch/powerpc/sysdev/Makefile b/arch/powerpc/sysdev/Makefile > index 026b3f01a991..7fc102222b77 100644 > --- a/arch/powerpc/sysdev/Makefile > +++ b/arch/powerpc/sysdev/Makefile > @@ -52,3 +52,5 @@ obj-$(CONFIG_PPC_XICS) += xics/ > obj-$(CONFIG_PPC_XIVE) += xive/ > > obj-$(CONFIG_GE_FPGA) += ge/ > + > +obj-$(CONFIG_MCE_ERROR_INJECT) += mce_error_inject.o > diff --git a/arch/powerpc/sysdev/mce_error_inject.c b/arch/powerpc/sysdev/mce_error_inject.c > new file mode 100644 > index 000000000000..ca4726bfa2d9 > --- /dev/null > +++ b/arch/powerpc/sysdev/mce_error_inject.c > @@ -0,0 +1,148 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Machine Check Exception injection code > + */ > + > +#include <linux/kernel.h> > +#include <linux/slab.h> > +#include <linux/vmalloc.h> > +#include <linux/fs.h> > +#include <linux/debugfs.h> > +#include <asm/debugfs.h> > + > +static inline unsigned long get_slb_index(void) > +{ > + unsigned long index; > + > + index = get_paca()->stab_rr; > + > + /* > + * simple round-robin replacement of slb starting at SLB_NUM_BOLTED. > + */ > + if (index < (mmu_slb_size - 1)) > + index++; > + else > + index = SLB_NUM_BOLTED; > + get_paca()->stab_rr = index; > + return index; > +} > + > +#define slb_esid_mask(ssize) \ > + (((ssize) == MMU_SEGSIZE_256M) ? ESID_MASK : ESID_MASK_1T) > + > +static inline unsigned long mk_esid_data(unsigned long ea, int ssize, > + unsigned long slot) > +{ > + return (ea & slb_esid_mask(ssize)) | SLB_ESID_V | slot; > +} > + > +#define slb_vsid_shift(ssize) \ > + ((ssize) == MMU_SEGSIZE_256M ? SLB_VSID_SHIFT : SLB_VSID_SHIFT_1T) > + > +static inline unsigned long mk_vsid_data(unsigned long ea, int ssize, > + unsigned long flags) > +{ > + return (get_kernel_vsid(ea, ssize) << slb_vsid_shift(ssize)) | flags | > + ((unsigned long)ssize << SLB_VSID_SSIZE_SHIFT); > +} > + > +static void insert_slb_entry(char *p, int ssize) > +{ > + unsigned long flags, entry; > + struct paca_struct *paca; > + > + flags = SLB_VSID_KERNEL | mmu_psize_defs[MMU_PAGE_64K].sllp; > + > + preempt_disable(); > + > + paca = get_paca(); This seems unused? > + > + entry = get_slb_index(); > + asm volatile("slbmte %0,%1" : > + : "r" (mk_vsid_data((unsigned long)p, ssize, flags)), > + "r" (mk_esid_data((unsigned long)p, ssize, entry)) > + : "memory"); > + > + entry = get_slb_index(); > + asm volatile("slbmte %0,%1" : > + : "r" (mk_vsid_data((unsigned long)p, ssize, flags)), > + "r" (mk_esid_data((unsigned long)p, ssize, entry)) > + : "memory"); > + preempt_enable(); > + p[0] = '!'; > +} > + > +static void inject_vmalloc_slb_multihit(void) > +{ > + char *p; > + > + p = vmalloc(2048); > + if (!p) > + return; > + > + insert_slb_entry(p, MMU_SEGSIZE_1T); > + vfree(p); > +} > + > +static void inject_kmalloc_slb_multihit(void) > +{ > + char *p; > + > + p = kmalloc(2048, GFP_KERNEL); > + if (!p) > + return; > + > + insert_slb_entry(p, MMU_SEGSIZE_1T); > + kfree(p); > +} > + > +static ssize_t inject_slb_multihit(const char __user *u_buf, size_t count) > +{ > + char buf[32]; > + size_t buf_size; > + > + buf_size = min(count, (sizeof(buf) - 1)); > + if (copy_from_user(buf, u_buf, buf_size)) > + return -EFAULT; > + buf[buf_size] = '\0'; > + > + if (buf[0] != '1') > + return -EINVAL; > + > + inject_vmalloc_slb_multihit(); > + inject_kmalloc_slb_multihit(); This is missing the test of multihit in paca which is for some reason special. Thanks Michal > + return count; > +} > + > +static ssize_t inject_write(struct file *file, const char __user *buf, > + size_t count, loff_t *ppos) > +{ > + static ssize_t (*func)(const char __user *, size_t); > + > + func = file->f_inode->i_private; > + return func(buf, count); > +} > + > +static const struct file_operations inject_fops = { > + .write = inject_write, > + .llseek = default_llseek, > +}; > + > +static int mce_error_inject_setup(void) > +{ > + struct dentry *mce_error_inject_dir; > + > + mce_error_inject_dir = debugfs_create_dir("mce_error_inject", > + powerpc_debugfs_root); > + > + if (mmu_has_feature(MMU_FTR_HPTE_TABLE)) { > + (void)debugfs_create_file("inject_slb_multihit", 0200, > + mce_error_inject_dir, > + &inject_slb_multihit, > + &inject_fops); > + } > + > + return 0; > +} > + > +device_initcall(mce_error_inject_setup); > -- > 2.26.2 >
Hi Ganesh, Ganesh Goudar <ganeshgr@linux.ibm.com> writes: > To test machine check handling, add debugfs interface to inject > slb multihit errors. > > To inject slb multihit: > #echo 1 > /sys/kernel/debug/powerpc/mce_error_inject/inject_slb_multihit Rather than creating a new ad-hoc way to trigger this, can you please integrate it into drivers/misc/lkdtm. There's enough code here that I think you should create drivers/misc/lkdtm/powerpc.c and put the code in there. Then add an LKDTM entry point for this, maybe called PPC_SLB_MULTIHIT. Please Cc Kees when you repost. cheers > arch/powerpc/Kconfig.debug | 9 ++ > arch/powerpc/sysdev/Makefile | 2 + > arch/powerpc/sysdev/mce_error_inject.c | 148 +++++++++++++++++++++++++ > 3 files changed, 159 insertions(+) > create mode 100644 arch/powerpc/sysdev/mce_error_inject.c > > diff --git a/arch/powerpc/Kconfig.debug b/arch/powerpc/Kconfig.debug > index b88900f4832f..61db133f2f0d 100644 > --- a/arch/powerpc/Kconfig.debug > +++ b/arch/powerpc/Kconfig.debug > @@ -398,3 +398,12 @@ config KASAN_SHADOW_OFFSET > hex > depends on KASAN > default 0xe0000000 > + > +config MCE_ERROR_INJECT > + bool "Enable MCE error injection through debugfs" > + depends on DEBUG_FS > + default y > + help > + This option creates an mce_error_inject directory in the > + powerpc debugfs directory that allows limited injection of > + Machine Check Errors (MCEs). > diff --git a/arch/powerpc/sysdev/Makefile b/arch/powerpc/sysdev/Makefile > index 026b3f01a991..7fc102222b77 100644 > --- a/arch/powerpc/sysdev/Makefile > +++ b/arch/powerpc/sysdev/Makefile > @@ -52,3 +52,5 @@ obj-$(CONFIG_PPC_XICS) += xics/ > obj-$(CONFIG_PPC_XIVE) += xive/ > > obj-$(CONFIG_GE_FPGA) += ge/ > + > +obj-$(CONFIG_MCE_ERROR_INJECT) += mce_error_inject.o > diff --git a/arch/powerpc/sysdev/mce_error_inject.c b/arch/powerpc/sysdev/mce_error_inject.c > new file mode 100644 > index 000000000000..ca4726bfa2d9 > --- /dev/null > +++ b/arch/powerpc/sysdev/mce_error_inject.c > @@ -0,0 +1,148 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Machine Check Exception injection code > + */ > + > +#include <linux/kernel.h> > +#include <linux/slab.h> > +#include <linux/vmalloc.h> > +#include <linux/fs.h> > +#include <linux/debugfs.h> > +#include <asm/debugfs.h> > + > +static inline unsigned long get_slb_index(void) > +{ > + unsigned long index; > + > + index = get_paca()->stab_rr; > + > + /* > + * simple round-robin replacement of slb starting at SLB_NUM_BOLTED. > + */ > + if (index < (mmu_slb_size - 1)) > + index++; > + else > + index = SLB_NUM_BOLTED; > + get_paca()->stab_rr = index; > + return index; > +} > + > +#define slb_esid_mask(ssize) \ > + (((ssize) == MMU_SEGSIZE_256M) ? ESID_MASK : ESID_MASK_1T) > + > +static inline unsigned long mk_esid_data(unsigned long ea, int ssize, > + unsigned long slot) > +{ > + return (ea & slb_esid_mask(ssize)) | SLB_ESID_V | slot; > +} > + > +#define slb_vsid_shift(ssize) \ > + ((ssize) == MMU_SEGSIZE_256M ? SLB_VSID_SHIFT : SLB_VSID_SHIFT_1T) > + > +static inline unsigned long mk_vsid_data(unsigned long ea, int ssize, > + unsigned long flags) > +{ > + return (get_kernel_vsid(ea, ssize) << slb_vsid_shift(ssize)) | flags | > + ((unsigned long)ssize << SLB_VSID_SSIZE_SHIFT); > +} > + > +static void insert_slb_entry(char *p, int ssize) > +{ > + unsigned long flags, entry; > + struct paca_struct *paca; > + > + flags = SLB_VSID_KERNEL | mmu_psize_defs[MMU_PAGE_64K].sllp; > + > + preempt_disable(); > + > + paca = get_paca(); > + > + entry = get_slb_index(); > + asm volatile("slbmte %0,%1" : > + : "r" (mk_vsid_data((unsigned long)p, ssize, flags)), > + "r" (mk_esid_data((unsigned long)p, ssize, entry)) > + : "memory"); > + > + entry = get_slb_index(); > + asm volatile("slbmte %0,%1" : > + : "r" (mk_vsid_data((unsigned long)p, ssize, flags)), > + "r" (mk_esid_data((unsigned long)p, ssize, entry)) > + : "memory"); > + preempt_enable(); > + p[0] = '!'; > +} > + > +static void inject_vmalloc_slb_multihit(void) > +{ > + char *p; > + > + p = vmalloc(2048); > + if (!p) > + return; > + > + insert_slb_entry(p, MMU_SEGSIZE_1T); > + vfree(p); > +} > + > +static void inject_kmalloc_slb_multihit(void) > +{ > + char *p; > + > + p = kmalloc(2048, GFP_KERNEL); > + if (!p) > + return; > + > + insert_slb_entry(p, MMU_SEGSIZE_1T); > + kfree(p); > +} > + > +static ssize_t inject_slb_multihit(const char __user *u_buf, size_t count) > +{ > + char buf[32]; > + size_t buf_size; > + > + buf_size = min(count, (sizeof(buf) - 1)); > + if (copy_from_user(buf, u_buf, buf_size)) > + return -EFAULT; > + buf[buf_size] = '\0'; > + > + if (buf[0] != '1') > + return -EINVAL; > + > + inject_vmalloc_slb_multihit(); > + inject_kmalloc_slb_multihit(); > + return count; > +} > + > +static ssize_t inject_write(struct file *file, const char __user *buf, > + size_t count, loff_t *ppos) > +{ > + static ssize_t (*func)(const char __user *, size_t); > + > + func = file->f_inode->i_private; > + return func(buf, count); > +} > + > +static const struct file_operations inject_fops = { > + .write = inject_write, > + .llseek = default_llseek, > +}; > + > +static int mce_error_inject_setup(void) > +{ > + struct dentry *mce_error_inject_dir; > + > + mce_error_inject_dir = debugfs_create_dir("mce_error_inject", > + powerpc_debugfs_root); > + > + if (mmu_has_feature(MMU_FTR_HPTE_TABLE)) { > + (void)debugfs_create_file("inject_slb_multihit", 0200, > + mce_error_inject_dir, > + &inject_slb_multihit, > + &inject_fops); > + } > + > + return 0; > +} > + > +device_initcall(mce_error_inject_setup); > -- > 2.26.2
On 9/17/20 5:53 PM, Michal Suchánek wrote: > Hello, > > On Wed, Sep 16, 2020 at 10:52:27PM +0530, Ganesh Goudar wrote: >> To test machine check handling, add debugfs interface to inject >> slb multihit errors. >> >> To inject slb multihit: >> #echo 1 > /sys/kernel/debug/powerpc/mce_error_inject/inject_slb_multihit >> >> Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com> >> Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> >> --- >> arch/powerpc/Kconfig.debug | 9 ++ >> arch/powerpc/sysdev/Makefile | 2 + >> arch/powerpc/sysdev/mce_error_inject.c | 148 +++++++++++++++++++++++++ >> 3 files changed, 159 insertions(+) >> create mode 100644 arch/powerpc/sysdev/mce_error_inject.c >> >> diff --git a/arch/powerpc/Kconfig.debug b/arch/powerpc/Kconfig.debug >> index b88900f4832f..61db133f2f0d 100644 >> --- a/arch/powerpc/Kconfig.debug >> +++ b/arch/powerpc/Kconfig.debug >> @@ -398,3 +398,12 @@ config KASAN_SHADOW_OFFSET >> hex >> depends on KASAN >> default 0xe0000000 >> + >> +config MCE_ERROR_INJECT >> + bool "Enable MCE error injection through debugfs" >> + depends on DEBUG_FS >> + default y >> + help >> + This option creates an mce_error_inject directory in the >> + powerpc debugfs directory that allows limited injection of >> + Machine Check Errors (MCEs). >> diff --git a/arch/powerpc/sysdev/Makefile b/arch/powerpc/sysdev/Makefile >> index 026b3f01a991..7fc102222b77 100644 >> --- a/arch/powerpc/sysdev/Makefile >> +++ b/arch/powerpc/sysdev/Makefile >> @@ -52,3 +52,5 @@ obj-$(CONFIG_PPC_XICS) += xics/ >> obj-$(CONFIG_PPC_XIVE) += xive/ >> >> obj-$(CONFIG_GE_FPGA) += ge/ >> + >> +obj-$(CONFIG_MCE_ERROR_INJECT) += mce_error_inject.o >> diff --git a/arch/powerpc/sysdev/mce_error_inject.c b/arch/powerpc/sysdev/mce_error_inject.c >> new file mode 100644 >> index 000000000000..ca4726bfa2d9 >> --- /dev/null >> +++ b/arch/powerpc/sysdev/mce_error_inject.c >> @@ -0,0 +1,148 @@ >> +// SPDX-License-Identifier: GPL-2.0 >> +/* >> + * Machine Check Exception injection code >> + */ >> + >> +#include <linux/kernel.h> >> +#include <linux/slab.h> >> +#include <linux/vmalloc.h> >> +#include <linux/fs.h> >> +#include <linux/debugfs.h> >> +#include <asm/debugfs.h> >> + >> +static inline unsigned long get_slb_index(void) >> +{ >> + unsigned long index; >> + >> + index = get_paca()->stab_rr; >> + >> + /* >> + * simple round-robin replacement of slb starting at SLB_NUM_BOLTED. >> + */ >> + if (index < (mmu_slb_size - 1)) >> + index++; >> + else >> + index = SLB_NUM_BOLTED; >> + get_paca()->stab_rr = index; >> + return index; >> +} >> + >> +#define slb_esid_mask(ssize) \ >> + (((ssize) == MMU_SEGSIZE_256M) ? ESID_MASK : ESID_MASK_1T) >> + >> +static inline unsigned long mk_esid_data(unsigned long ea, int ssize, >> + unsigned long slot) >> +{ >> + return (ea & slb_esid_mask(ssize)) | SLB_ESID_V | slot; >> +} >> + >> +#define slb_vsid_shift(ssize) \ >> + ((ssize) == MMU_SEGSIZE_256M ? SLB_VSID_SHIFT : SLB_VSID_SHIFT_1T) >> + >> +static inline unsigned long mk_vsid_data(unsigned long ea, int ssize, >> + unsigned long flags) >> +{ >> + return (get_kernel_vsid(ea, ssize) << slb_vsid_shift(ssize)) | flags | >> + ((unsigned long)ssize << SLB_VSID_SSIZE_SHIFT); >> +} >> + >> +static void insert_slb_entry(char *p, int ssize) >> +{ >> + unsigned long flags, entry; >> + struct paca_struct *paca; >> + >> + flags = SLB_VSID_KERNEL | mmu_psize_defs[MMU_PAGE_64K].sllp; >> + >> + preempt_disable(); >> + >> + paca = get_paca(); > This seems unused? Thanks, ill remove it. >> + >> + entry = get_slb_index(); >> + asm volatile("slbmte %0,%1" : >> + : "r" (mk_vsid_data((unsigned long)p, ssize, flags)), >> + "r" (mk_esid_data((unsigned long)p, ssize, entry)) >> + : "memory"); >> + >> + entry = get_slb_index(); >> + asm volatile("slbmte %0,%1" : >> + : "r" (mk_vsid_data((unsigned long)p, ssize, flags)), >> + "r" (mk_esid_data((unsigned long)p, ssize, entry)) >> + : "memory"); >> + preempt_enable(); >> + p[0] = '!'; >> +} >> + >> +static void inject_vmalloc_slb_multihit(void) >> +{ >> + char *p; >> + >> + p = vmalloc(2048); >> + if (!p) >> + return; >> + >> + insert_slb_entry(p, MMU_SEGSIZE_1T); >> + vfree(p); >> +} >> + >> +static void inject_kmalloc_slb_multihit(void) >> +{ >> + char *p; >> + >> + p = kmalloc(2048, GFP_KERNEL); >> + if (!p) >> + return; >> + >> + insert_slb_entry(p, MMU_SEGSIZE_1T); >> + kfree(p); >> +} >> + >> +static ssize_t inject_slb_multihit(const char __user *u_buf, size_t count) >> +{ >> + char buf[32]; >> + size_t buf_size; >> + >> + buf_size = min(count, (sizeof(buf) - 1)); >> + if (copy_from_user(buf, u_buf, buf_size)) >> + return -EFAULT; >> + buf[buf_size] = '\0'; >> + >> + if (buf[0] != '1') >> + return -EINVAL; >> + >> + inject_vmalloc_slb_multihit(); >> + inject_kmalloc_slb_multihit(); > This is missing the test of multihit in paca which is for some reason > special. I will add it, Thanks > Thanks > > Michal >> + return count; >> +} >> + >> +static ssize_t inject_write(struct file *file, const char __user *buf, >> + size_t count, loff_t *ppos) >> +{ >> + static ssize_t (*func)(const char __user *, size_t); >> + >> + func = file->f_inode->i_private; >> + return func(buf, count); >> +} >> + >> +static const struct file_operations inject_fops = { >> + .write = inject_write, >> + .llseek = default_llseek, >> +}; >> + >> +static int mce_error_inject_setup(void) >> +{ >> + struct dentry *mce_error_inject_dir; >> + >> + mce_error_inject_dir = debugfs_create_dir("mce_error_inject", >> + powerpc_debugfs_root); >> + >> + if (mmu_has_feature(MMU_FTR_HPTE_TABLE)) { >> + (void)debugfs_create_file("inject_slb_multihit", 0200, >> + mce_error_inject_dir, >> + &inject_slb_multihit, >> + &inject_fops); >> + } >> + >> + return 0; >> +} >> + >> +device_initcall(mce_error_inject_setup); >> -- >> 2.26.2 >>
On 9/18/20 12:10 PM, Michael Ellerman wrote: > Hi Ganesh, > > Ganesh Goudar <ganeshgr@linux.ibm.com> writes: >> To test machine check handling, add debugfs interface to inject >> slb multihit errors. >> >> To inject slb multihit: >> #echo 1 > /sys/kernel/debug/powerpc/mce_error_inject/inject_slb_multihit > Rather than creating a new ad-hoc way to trigger this, can you please > integrate it into drivers/misc/lkdtm. > > There's enough code here that I think you should create > drivers/misc/lkdtm/powerpc.c and put the code in there. Then add an > LKDTM entry point for this, maybe called PPC_SLB_MULTIHIT. > > Please Cc Kees when you repost. Sure, Thanks > cheers > > >> arch/powerpc/Kconfig.debug | 9 ++ >> arch/powerpc/sysdev/Makefile | 2 + >> arch/powerpc/sysdev/mce_error_inject.c | 148 +++++++++++++++++++++++++ >> 3 files changed, 159 insertions(+) >> create mode 100644 arch/powerpc/sysdev/mce_error_inject.c >> >> diff --git a/arch/powerpc/Kconfig.debug b/arch/powerpc/Kconfig.debug >> index b88900f4832f..61db133f2f0d 100644 >> --- a/arch/powerpc/Kconfig.debug >> +++ b/arch/powerpc/Kconfig.debug >> @@ -398,3 +398,12 @@ config KASAN_SHADOW_OFFSET >> hex >> depends on KASAN >> default 0xe0000000 >> + >> +config MCE_ERROR_INJECT >> + bool "Enable MCE error injection through debugfs" >> + depends on DEBUG_FS >> + default y >> + help >> + This option creates an mce_error_inject directory in the >> + powerpc debugfs directory that allows limited injection of >> + Machine Check Errors (MCEs). >> diff --git a/arch/powerpc/sysdev/Makefile b/arch/powerpc/sysdev/Makefile >> index 026b3f01a991..7fc102222b77 100644 >> --- a/arch/powerpc/sysdev/Makefile >> +++ b/arch/powerpc/sysdev/Makefile >> @@ -52,3 +52,5 @@ obj-$(CONFIG_PPC_XICS) += xics/ >> obj-$(CONFIG_PPC_XIVE) += xive/ >> >> obj-$(CONFIG_GE_FPGA) += ge/ >> + >> +obj-$(CONFIG_MCE_ERROR_INJECT) += mce_error_inject.o >> diff --git a/arch/powerpc/sysdev/mce_error_inject.c b/arch/powerpc/sysdev/mce_error_inject.c >> new file mode 100644 >> index 000000000000..ca4726bfa2d9 >> --- /dev/null >> +++ b/arch/powerpc/sysdev/mce_error_inject.c >> @@ -0,0 +1,148 @@ >> +// SPDX-License-Identifier: GPL-2.0 >> +/* >> + * Machine Check Exception injection code >> + */ >> + >> +#include <linux/kernel.h> >> +#include <linux/slab.h> >> +#include <linux/vmalloc.h> >> +#include <linux/fs.h> >> +#include <linux/debugfs.h> >> +#include <asm/debugfs.h> >> + >> +static inline unsigned long get_slb_index(void) >> +{ >> + unsigned long index; >> + >> + index = get_paca()->stab_rr; >> + >> + /* >> + * simple round-robin replacement of slb starting at SLB_NUM_BOLTED. >> + */ >> + if (index < (mmu_slb_size - 1)) >> + index++; >> + else >> + index = SLB_NUM_BOLTED; >> + get_paca()->stab_rr = index; >> + return index; >> +} >> + >> +#define slb_esid_mask(ssize) \ >> + (((ssize) == MMU_SEGSIZE_256M) ? ESID_MASK : ESID_MASK_1T) >> + >> +static inline unsigned long mk_esid_data(unsigned long ea, int ssize, >> + unsigned long slot) >> +{ >> + return (ea & slb_esid_mask(ssize)) | SLB_ESID_V | slot; >> +} >> + >> +#define slb_vsid_shift(ssize) \ >> + ((ssize) == MMU_SEGSIZE_256M ? SLB_VSID_SHIFT : SLB_VSID_SHIFT_1T) >> + >> +static inline unsigned long mk_vsid_data(unsigned long ea, int ssize, >> + unsigned long flags) >> +{ >> + return (get_kernel_vsid(ea, ssize) << slb_vsid_shift(ssize)) | flags | >> + ((unsigned long)ssize << SLB_VSID_SSIZE_SHIFT); >> +} >> + >> +static void insert_slb_entry(char *p, int ssize) >> +{ >> + unsigned long flags, entry; >> + struct paca_struct *paca; >> + >> + flags = SLB_VSID_KERNEL | mmu_psize_defs[MMU_PAGE_64K].sllp; >> + >> + preempt_disable(); >> + >> + paca = get_paca(); >> + >> + entry = get_slb_index(); >> + asm volatile("slbmte %0,%1" : >> + : "r" (mk_vsid_data((unsigned long)p, ssize, flags)), >> + "r" (mk_esid_data((unsigned long)p, ssize, entry)) >> + : "memory"); >> + >> + entry = get_slb_index(); >> + asm volatile("slbmte %0,%1" : >> + : "r" (mk_vsid_data((unsigned long)p, ssize, flags)), >> + "r" (mk_esid_data((unsigned long)p, ssize, entry)) >> + : "memory"); >> + preempt_enable(); >> + p[0] = '!'; >> +} >> + >> +static void inject_vmalloc_slb_multihit(void) >> +{ >> + char *p; >> + >> + p = vmalloc(2048); >> + if (!p) >> + return; >> + >> + insert_slb_entry(p, MMU_SEGSIZE_1T); >> + vfree(p); >> +} >> + >> +static void inject_kmalloc_slb_multihit(void) >> +{ >> + char *p; >> + >> + p = kmalloc(2048, GFP_KERNEL); >> + if (!p) >> + return; >> + >> + insert_slb_entry(p, MMU_SEGSIZE_1T); >> + kfree(p); >> +} >> + >> +static ssize_t inject_slb_multihit(const char __user *u_buf, size_t count) >> +{ >> + char buf[32]; >> + size_t buf_size; >> + >> + buf_size = min(count, (sizeof(buf) - 1)); >> + if (copy_from_user(buf, u_buf, buf_size)) >> + return -EFAULT; >> + buf[buf_size] = '\0'; >> + >> + if (buf[0] != '1') >> + return -EINVAL; >> + >> + inject_vmalloc_slb_multihit(); >> + inject_kmalloc_slb_multihit(); >> + return count; >> +} >> + >> +static ssize_t inject_write(struct file *file, const char __user *buf, >> + size_t count, loff_t *ppos) >> +{ >> + static ssize_t (*func)(const char __user *, size_t); >> + >> + func = file->f_inode->i_private; >> + return func(buf, count); >> +} >> + >> +static const struct file_operations inject_fops = { >> + .write = inject_write, >> + .llseek = default_llseek, >> +}; >> + >> +static int mce_error_inject_setup(void) >> +{ >> + struct dentry *mce_error_inject_dir; >> + >> + mce_error_inject_dir = debugfs_create_dir("mce_error_inject", >> + powerpc_debugfs_root); >> + >> + if (mmu_has_feature(MMU_FTR_HPTE_TABLE)) { >> + (void)debugfs_create_file("inject_slb_multihit", 0200, >> + mce_error_inject_dir, >> + &inject_slb_multihit, >> + &inject_fops); >> + } >> + >> + return 0; >> +} >> + >> +device_initcall(mce_error_inject_setup); >> -- >> 2.26.2
diff --git a/arch/powerpc/Kconfig.debug b/arch/powerpc/Kconfig.debug index b88900f4832f..61db133f2f0d 100644 --- a/arch/powerpc/Kconfig.debug +++ b/arch/powerpc/Kconfig.debug @@ -398,3 +398,12 @@ config KASAN_SHADOW_OFFSET hex depends on KASAN default 0xe0000000 + +config MCE_ERROR_INJECT + bool "Enable MCE error injection through debugfs" + depends on DEBUG_FS + default y + help + This option creates an mce_error_inject directory in the + powerpc debugfs directory that allows limited injection of + Machine Check Errors (MCEs). diff --git a/arch/powerpc/sysdev/Makefile b/arch/powerpc/sysdev/Makefile index 026b3f01a991..7fc102222b77 100644 --- a/arch/powerpc/sysdev/Makefile +++ b/arch/powerpc/sysdev/Makefile @@ -52,3 +52,5 @@ obj-$(CONFIG_PPC_XICS) += xics/ obj-$(CONFIG_PPC_XIVE) += xive/ obj-$(CONFIG_GE_FPGA) += ge/ + +obj-$(CONFIG_MCE_ERROR_INJECT) += mce_error_inject.o diff --git a/arch/powerpc/sysdev/mce_error_inject.c b/arch/powerpc/sysdev/mce_error_inject.c new file mode 100644 index 000000000000..ca4726bfa2d9 --- /dev/null +++ b/arch/powerpc/sysdev/mce_error_inject.c @@ -0,0 +1,148 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Machine Check Exception injection code + */ + +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/vmalloc.h> +#include <linux/fs.h> +#include <linux/debugfs.h> +#include <asm/debugfs.h> + +static inline unsigned long get_slb_index(void) +{ + unsigned long index; + + index = get_paca()->stab_rr; + + /* + * simple round-robin replacement of slb starting at SLB_NUM_BOLTED. + */ + if (index < (mmu_slb_size - 1)) + index++; + else + index = SLB_NUM_BOLTED; + get_paca()->stab_rr = index; + return index; +} + +#define slb_esid_mask(ssize) \ + (((ssize) == MMU_SEGSIZE_256M) ? ESID_MASK : ESID_MASK_1T) + +static inline unsigned long mk_esid_data(unsigned long ea, int ssize, + unsigned long slot) +{ + return (ea & slb_esid_mask(ssize)) | SLB_ESID_V | slot; +} + +#define slb_vsid_shift(ssize) \ + ((ssize) == MMU_SEGSIZE_256M ? SLB_VSID_SHIFT : SLB_VSID_SHIFT_1T) + +static inline unsigned long mk_vsid_data(unsigned long ea, int ssize, + unsigned long flags) +{ + return (get_kernel_vsid(ea, ssize) << slb_vsid_shift(ssize)) | flags | + ((unsigned long)ssize << SLB_VSID_SSIZE_SHIFT); +} + +static void insert_slb_entry(char *p, int ssize) +{ + unsigned long flags, entry; + struct paca_struct *paca; + + flags = SLB_VSID_KERNEL | mmu_psize_defs[MMU_PAGE_64K].sllp; + + preempt_disable(); + + paca = get_paca(); + + entry = get_slb_index(); + asm volatile("slbmte %0,%1" : + : "r" (mk_vsid_data((unsigned long)p, ssize, flags)), + "r" (mk_esid_data((unsigned long)p, ssize, entry)) + : "memory"); + + entry = get_slb_index(); + asm volatile("slbmte %0,%1" : + : "r" (mk_vsid_data((unsigned long)p, ssize, flags)), + "r" (mk_esid_data((unsigned long)p, ssize, entry)) + : "memory"); + preempt_enable(); + p[0] = '!'; +} + +static void inject_vmalloc_slb_multihit(void) +{ + char *p; + + p = vmalloc(2048); + if (!p) + return; + + insert_slb_entry(p, MMU_SEGSIZE_1T); + vfree(p); +} + +static void inject_kmalloc_slb_multihit(void) +{ + char *p; + + p = kmalloc(2048, GFP_KERNEL); + if (!p) + return; + + insert_slb_entry(p, MMU_SEGSIZE_1T); + kfree(p); +} + +static ssize_t inject_slb_multihit(const char __user *u_buf, size_t count) +{ + char buf[32]; + size_t buf_size; + + buf_size = min(count, (sizeof(buf) - 1)); + if (copy_from_user(buf, u_buf, buf_size)) + return -EFAULT; + buf[buf_size] = '\0'; + + if (buf[0] != '1') + return -EINVAL; + + inject_vmalloc_slb_multihit(); + inject_kmalloc_slb_multihit(); + return count; +} + +static ssize_t inject_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + static ssize_t (*func)(const char __user *, size_t); + + func = file->f_inode->i_private; + return func(buf, count); +} + +static const struct file_operations inject_fops = { + .write = inject_write, + .llseek = default_llseek, +}; + +static int mce_error_inject_setup(void) +{ + struct dentry *mce_error_inject_dir; + + mce_error_inject_dir = debugfs_create_dir("mce_error_inject", + powerpc_debugfs_root); + + if (mmu_has_feature(MMU_FTR_HPTE_TABLE)) { + (void)debugfs_create_file("inject_slb_multihit", 0200, + mce_error_inject_dir, + &inject_slb_multihit, + &inject_fops); + } + + return 0; +} + +device_initcall(mce_error_inject_setup);