Re: [PATCH 5/6] edac, mce_amd_inj: Add README file

Borislav Petkov
2015-05-29T15:38:57Z

On Wed, May 27, 2015 at 02:03:37PM -0500, Aravind Gopalakrishnan wrote:
> Provides information about each file and the usages.
>
> Signed-off-by: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>
> ---
> drivers/edac/mce_amd_inj.c | 68 +++++++++++++++++++++++++++++++++++++++++-----
> 1 file changed, 61 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/edac/mce_amd_inj.c b/drivers/edac/mce_amd_inj.c
> index f1c1433..ca5b29f 100644
> --- a/drivers/edac/mce_amd_inj.c
> +++ b/drivers/edac/mce_amd_inj.c
> @@ -291,17 +291,71 @@ MCE_INJECT_GET(bank);
>
> DEFINE_SIMPLE_ATTRIBUTE(bank_fops, inj_bank_get, inj_bank_set, "%llu\n");
>
> +static const char readme_msg[] =
> + "\nDescription of the files and their usages:\n\n"
> + "status: Set a value to be programmed into MCx_STATUS(bank)\n"
> + "\t The status bits provide insight into the type of\n"
> + "\t error that caused the MCE.\n\n"
> + "misc: Set value of MCx_MISC(bank)\n"
> + "\t misc register provides auxiliary info about the error. This\n"
> + "\t register is typically used for error thresholding purpose and\n"
> + "\t validity of the register is indicated by MCx_STATUS[MiscV]\n\n"
> + "addr: Error address value to be written to MCx_ADDR(bank)\n"
> + "\t This register is used to log address information associated\n"
> + "\t with the error.\n\n"
> + "Note: See respective BKDGs for the exact bit definitions of the\n"
> + "\t above registers as they mirror the MCi_[STATUS | MISC | ADDR]\n"
> + "\t hardware registers.\n\n"
> + "bank: Specify the bank you want to inject the error into.\n"
> + "\t The number of banks in a processor varies and is family/model\n"
> + "\t dependent. So, a sanity check performed while writing.\n"
> + "\t Writing to this file will trigger a #MC or APIC interrupts or\n"
> + "\t invoke the error decoder routines for AMD processors. The value\n"
> + "\t in 'flags' file decides which of above actions is triggered.\n\n"
> + "flags: Write to this file to speficy the error injection policy.\n"
> + "\t Allowed values:\n"
> + "\t\t\"sw\" - SW error injection, Only calls error decoder\n"
> + "\t\t\troutines to print error info in human readable format\n"
> + "\t\t\"hw\" - HW error injection, Forces a #MC,\n"
> + "\t\t\tcauses exception handler to handle the error\n"
> + "\t\t\tif UC or poll handler catches it if CE\n"
> + "\t\t\tWarning: Might cause system panic if MCx_STATUS[PCC]\n"
> + "\t\t\tis set. For debug purposes, consider setting\n"
> + "\t\t\t/<debugfs_mountpoint>/mce/fake_panic\n"
> + "\t\t\"dfr\" - Trigger APIC interrupt for Deferred error\n"
> + "\t\t\tError is handled by deferred error apic handler if\n"
> + "\t\t\tfeature is present in HW.\n"
> + "\t\t\"thr\" - Trigger APIC interrupt for threshold error\n"
> + "\t\t\tError is handled by threshold apic handler\n\n"
> + "cpu: The cpu to inject the error on.\n\n"
> +;

This one needs to be split in two - the second one adding the readme file...

> +static ssize_t
> +inj_readme_read(struct file *filp, char __user *ubuf,
> + size_t cnt, loff_t *ppos)
> +{
> + return simple_read_from_buffer(ubuf, cnt, ppos,
> + readme_msg, strlen(readme_msg));
> +}
> +
> +static const struct file_operations readme_fops = {
> + .read = inj_readme_read,
> +};
> +
> static struct dfs_node {
> char *name;
> struct dentry *d;
> const struct file_operations *fops;
> + umode_t perm;
> } dfs_fls[] = {
> - { .name = "status", .fops = &status_fops },
> - { .name = "misc", .fops = &misc_fops },
> - { .name = "addr", .fops = &addr_fops },
> - { .name = "bank", .fops = &bank_fops },
> - { .name = "flags", .fops = &flags_fops },
> - { .name = "cpu", .fops = &extcpu_fops },
> + { .name = "status", .fops = &status_fops, S_IRUSR | S_IWUSR },
> + { .name = "misc", .fops = &misc_fops, S_IRUSR | S_IWUSR },
> + { .name = "addr", .fops = &addr_fops, S_IRUSR | S_IWUSR },
> + { .name = "bank", .fops = &bank_fops, S_IRUSR | S_IWUSR },
> + { .name = "flags", .fops = &flags_fops, S_IRUSR | S_IWUSR },
> + { .name = "cpu", .fops = &extcpu_fops, S_IRUSR | S_IWUSR },
> + { .name = "README", .fops = &readme_fops, S_IRUSR | S_IRGRP |
> + S_IROTH },

... and the first one adding perm to struct dfs_node.

--
Regards/Gruss,
Boris.

ECO tip #101: Trim your mails when you reply.
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