diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/edac.txt | 56 |
1 files changed, 29 insertions, 27 deletions
diff --git a/Documentation/edac.txt b/Documentation/edac.txt index bd3f8a3905af..0b875e8da969 100644 --- a/Documentation/edac.txt +++ b/Documentation/edac.txt @@ -766,7 +766,7 @@ exports one For injecting a memory error, there are some sysfs nodes, under /sys/devices/system/edac/mc/mc?/: - inject_addrmatch: + inject_addrmatch/*: Controls the error injection mask register. It is possible to specify several characteristics of the address to match an error code: dimm = the affected dimm. Numbers are relative to a channel; @@ -781,10 +781,12 @@ exports one For example, to generate an error at rank 1 of dimm 2, for any channel, any bank, any page, any column: - echo "dimm:2 rank:1" >/sys/devices/system/edac/mc/mc0/inject_addrmatch + echo 2 >/sys/devices/system/edac/mc/mc0/inject_addrmatch/dimm + echo 1 >/sys/devices/system/edac/mc/mc0/inject_addrmatch/rank To return to the default behaviour of matching any, you can do: - echo "dimm:any rank:any" >/sys/devices/system/edac/mc/mc0/inject_addrmatch + echo any >/sys/devices/system/edac/mc/mc0/inject_addrmatch/dimm + echo any >/sys/devices/system/edac/mc/mc0/inject_addrmatch/rank inject_eccmask: specifies what bits will have troubles, @@ -813,7 +815,7 @@ exports one For example, the following code will generate an error for any write access at socket 0, on any DIMM/address on channel 2: - echo "channel:2" > /sys/devices/system/edac/mc/mc0/inject_addrmatch + echo 2 >/sys/devices/system/edac/mc/mc0/inject_addrmatch/channel echo 2 >/sys/devices/system/edac/mc/mc0/inject_type echo 64 >/sys/devices/system/edac/mc/mc0/inject_eccmask echo 3 >/sys/devices/system/edac/mc/mc0/inject_section @@ -829,18 +831,23 @@ exports one 3) Nehalem specific Corrected Error memory counters - Nehalem have some registers to count memory errors, reporting it on a - way that it is different from what EDAC API allows. Due to that, a - separate sysfs note were created to handle such counters. + Nehalem have some registers to count memory errors. The driver uses those + registers to report Corrected Errors on devices with Registered Dimms. - They can be read by looking at the contents of "corrected_error_counts" - counter. Due to hardware limits, the output is different on machines - with unregistered memories and machines with registered ones. + However, those counters don't work with Unregistered Dimms. As the chipset + offers some counters that also work with UDIMMS (but with a worse level of + granularity than the default ones), the driver exposes those registers for + UDIMM memories. - With unregistered memories, it outputs: + They can be read by looking at the contents of all_channel_counts/ - $ cat /sys/devices/system/edac/mc/mc0/corrected_error_counts - all channels UDIMM0: 0 UDIMM1: 0 UDIMM2: 0 + $ for i in /sys/devices/system/edac/mc/mc0/all_channel_counts/*; do echo $i; cat $i; done + /sys/devices/system/edac/mc/mc0/all_channel_counts/udimm0 + 0 + /sys/devices/system/edac/mc/mc0/all_channel_counts/udimm1 + 0 + /sys/devices/system/edac/mc/mc0/all_channel_counts/udimm2 + 0 What happens here is that errors on different csrows, but at the same dimm number will increment the same counter. @@ -849,21 +856,16 @@ exports one csrow1: channel 0, dimm1 csrow2: channel 1, dimm0 csrow3: channel 2, dimm0 - The hardware will increment UDIMM0 for an error at either csrow0, csrow2 - or csrow3. - - With registered memories, it outputs: - - $cat /sys/devices/system/edac/mc/mc0/corrected_error_counts - channel 0 RDIMM0: 0 RDIMM1: 0 RDIMM2: 0 - channel 1 RDIMM0: 0 RDIMM1: 0 RDIMM2: 0 - channel 2 RDIMM0: 0 RDIMM1: 0 RDIMM2: 0 - - So, with registered memories, there's a direct map between a csrow and a - counter. + The hardware will increment udimm0 for an error at the first dimm at either + csrow0, csrow2 or csrow3; + The hardware will increment udimm1 for an error at the second dimm at either + csrow0, csrow2 or csrow3; + The hardware will increment udimm2 for an error at the third dimm at either + csrow0, csrow2 or csrow3; 4) Standard error counters The standard error counters are generated when an mcelog error is received - by the driver. Since it is counted by software, it is possible that some - errors could be lost. + by the driver. Since, with udimm, this is counted by software, it is + possible that some errors could be lost. With rdimm's, they displays the + contents of the registers |