linux/drivers/ras, branch v5.3

RAS/CEC: Add copyright

2019-06-08T15:40:28Z

Signed-off-by: Borislav Petkov

RAS/CEC: Add CONFIG_RAS_CEC_DEBUG and move CEC debug features there

2019-06-08T15:39:24Z

The pfn and array files in (debugfs)/ras/cec are intended for debugging the CEC code itself. They are not needed on production systems, so the default setting for this CONFIG option is "n". [ bp: Have it with less ifdeffery by using IS_ENABLED(). ] Signed-off-by: Tony Luck Signed-off-by: Borislav Petkov

RAS/CEC: Dump the different array element sections

2019-06-08T15:39:11Z

When dumping the array elements, print them in the following format: [ PFN | generation in binary | count ] to be perfectly clear what all those sections are. Signed-off-by: Borislav Petkov Cc: Tony Luck Cc: linux-edac

RAS/CEC: Rename count_threshold to action_threshold

2019-06-08T15:38:17Z

... which is the better, more-fitting name anyway. Tony: - make action_threshold u64 due to debugfs accessors expecting u64. - rename the remaining: s/count_threshold/action_threshold/g Co-developed-by: Tony Luck Signed-off-by: Tony Luck Signed-off-by: Borislav Petkov Cc: linux-edac

RAS/CEC: Sanity-check array on every insertion

2019-06-08T15:35:34Z

Check the elements order in the array after every insertion. Signed-off-by: Borislav Petkov Cc: Tony Luck Cc: linux-edac

RAS/CEC: Fix potential memory leak

2019-06-08T15:35:04Z

Free the array page if a failure is encountered while creating the debugfs nodes. Signed-off-by: Borislav Petkov Cc: Tony Luck Cc: linux-edac

RAS/CEC: Do not set decay value on error

2019-06-08T15:34:36Z

When the value requested doesn't match the allowed (min,max) range, the @data buffer should not be modified with the invalid value because reading "decay_interval" shows it otherwise as if the previous write succeeded. Move the data write after the check. Signed-off-by: Borislav Petkov Cc: Tony Luck Cc: linux-edac

RAS/CEC: Check count_threshold unconditionally

2019-06-08T15:33:10Z

The count_threshold should be checked unconditionally, after insertion too, so that a count_threshold value of 1 can cause an immediate offlining. I.e., offline the page on the *first* error encountered. Add comments to make it clear what cec_add_elem() does, while at it. Reported-by: WANG Chao Signed-off-by: Borislav Petkov Cc: Tony Luck Cc: linux-edac@vger.kernel.org Link: https://lkml.kernel.org/r/20190418034115.75954-3-chao.wang@ucloud.cn

RAS/CEC: Fix pfn insertion

2019-06-08T15:32:00Z

When inserting random PFNs for debugging the CEC through (debugfs)/ras/cec/pfn, depending on the return value of pfn_set(), multiple values get inserted per a single write. That is because simple_attr_write() interprets a retval of 0 as success and claims the whole input. However, pfn_set() returns the cec_add_elem() value, which, if > 0 and smaller than the whole input length, makes glibc continue issuing the write syscall until there's input left: pfn_set simple_attr_write debugfs_attr_write full_proxy_write vfs_write ksys_write do_syscall_64 entry_SYSCALL_64_after_hwframe leading to those repeated calls. Return 0 to fix that. Signed-off-by: Borislav Petkov Cc: Tony Luck Cc: linux-edac

RAS/CEC: Convert the timer callback to a workqueue

2019-06-07T21:21:39Z

cec_timer_fn() is a timer callback which reads ce_arr.array[] and updates its decay values. However, it runs in interrupt context and the mutex protection the CEC uses for that array, is inadequate. Convert the used timer to a workqueue to keep the tasks the CEC performs preemptible and thus low-prio. [ bp: Rewrite commit message. s/timer/decay/gi to make it agnostic as to what facility is used. ] Fixes: 011d82611172 ("RAS: Add a Corrected Errors Collector") Signed-off-by: Cong Wang Signed-off-by: Borislav Petkov Cc: Thomas Gleixner Cc: Tony Luck Cc: linux-edac Cc: Link: https://lkml.kernel.org/r/20190416213351.28999-2-xiyou.wangcong@gmail.com