Re: [PATCH v5 0/9] efi/cxl-cper: Report CPER CXL component events through trace events

From: Dan Williams
Date: Mon Jan 08 2024 - 21:08:32 EST


Smita Koralahalli wrote:
> On 1/8/2024 8:58 AM, Jonathan Cameron wrote:
> > On Wed, 20 Dec 2023 16:17:27 -0800
> > Ira Weiny <ira.weiny@xxxxxxxxx> wrote:
> >
> >> Series status/background
> >> ========================
> >>
> >> Smita has been a great help with this series. Thank you again!
> >>
> >> Smita's testing found that the GHES code ended up printing the events
> >> twice. This version avoids the duplicate print by calling the callback
> >> from the GHES code instead of the EFI code as suggested by Dan.
> >
> > I'm not sure this is working as intended.
> >
> > There is nothing gating the call in ghes_proc() of ghes_print_estatus()
> > and now the EFI code handling that pretty printed things is missing we get
> > the horrible kernel logging for an unknown block instead.
> >
> > So I think we need some minimal code in cper.c to match the guids then not
> > log them (on basis we are arguing there is no need for new cper records).
> > Otherwise we are in for some messy kernel logs
> >
> > Something like:
> >
> > {1}[Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 1
> > {1}[Hardware Error]: event severity: recoverable
> > {1}[Hardware Error]: Error 0, type: recoverable
> > {1}[Hardware Error]: section type: unknown, fbcd0a77-c260-417f-85a9-088b1621eba6
> > {1}[Hardware Error]: section length: 0x90
> > {1}[Hardware Error]: 00000000: 00000090 00000007 00000000 0d938086 ................
> > {1}[Hardware Error]: 00000010: 00100000 00000000 00040000 00000000 ................
> > {1}[Hardware Error]: 00000020: 00000000 00000000 00000000 00000000 ................
> > {1}[Hardware Error]: 00000030: 00000000 00000000 00000000 00000000 ................
> > {1}[Hardware Error]: 00000040: 00000000 00000000 00000000 00000000 ................
> > {1}[Hardware Error]: 00000050: 00000000 00000000 00000000 00000000 ................
> > {1}[Hardware Error]: 00000060: 00000000 00000000 00000000 00000000 ................
> > {1}[Hardware Error]: 00000070: 00000000 00000000 00000000 00000000 ................
> > {1}[Hardware Error]: 00000080: 00000000 00000000 00000000 00000000 ................
> > cxl_general_media: memdev=mem1 host=0000:10:00.0 serial=4 log=Informational : time=0 uuid=fbcd0a77-c260-417f-85a9-088b1621eba6 len=0 flags='' handle=0 related_handle=0 maint_op_class=0 : dpa=0 dpa_flags='' descriptor='' type='ECC Error' transaction_type='Unknown' channel=0 rank=0 device=0 comp_id=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 validity_flags=''
> >
> > (I'm filling the record with 0s currently)
>
> Yeah, when I tested this, I thought its okay for the hexdump to be there
> in dmesg from EFI as the handling is done in trace events from GHES.
>
> If, we need to handle from EFI, then it would be a good reason to move
> the GUIDs out from GHES and place it in a common location for EFI/cper
> to share similar to protocol errors.

Ah, yes, my expectation was more aligned with Jonathan's observation to
do the processing in GHES code *and* skip the processing in the CPER
code, something like:


diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
index 56a5d2ef9e0a..e13e5fa4df4b 100644
--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c
@@ -666,30 +666,6 @@ static cxl_cper_callback cper_callback;

/* CXL Event record UUIDs are formatted as GUIDs and reported in section type */

-/*
- * General Media Event Record
- * CXL rev 3.0 Section 8.2.9.2.1.1; Table 8-43
- */
-#define CPER_SEC_CXL_GEN_MEDIA_GUID \
- GUID_INIT(0xfbcd0a77, 0xc260, 0x417f, \
- 0x85, 0xa9, 0x08, 0x8b, 0x16, 0x21, 0xeb, 0xa6)
-
-/*
- * DRAM Event Record
- * CXL rev 3.0 section 8.2.9.2.1.2; Table 8-44
- */
-#define CPER_SEC_CXL_DRAM_GUID \
- GUID_INIT(0x601dcbb3, 0x9c06, 0x4eab, \
- 0xb8, 0xaf, 0x4e, 0x9b, 0xfb, 0x5c, 0x96, 0x24)
-
-/*
- * Memory Module Event Record
- * CXL rev 3.0 section 8.2.9.2.1.3; Table 8-45
- */
-#define CPER_SEC_CXL_MEM_MODULE_GUID \
- GUID_INIT(0xfe927475, 0xdd59, 0x4339, \
- 0xa5, 0x86, 0x79, 0xba, 0xb1, 0x13, 0xb7, 0x74)
-
static void cxl_cper_post_event(enum cxl_event_type event_type,
struct cxl_cper_event_rec *rec)
{
diff --git a/drivers/firmware/efi/cper.c b/drivers/firmware/efi/cper.c
index 35c37f667781..0a4eed470750 100644
--- a/drivers/firmware/efi/cper.c
+++ b/drivers/firmware/efi/cper.c
@@ -24,6 +24,7 @@
#include <linux/bcd.h>
#include <acpi/ghes.h>
#include <ras/ras_event.h>
+#include <linux/cxl-event.h>
#include "cper_cxl.h"

/*
@@ -607,6 +608,15 @@ cper_estatus_print_section(const char *pfx, struct acpi_hest_generic_data *gdata
cper_print_prot_err(newpfx, prot_err);
else
goto err_section_too_small;
+ } else if (guid_equal(sec_type, &CPER_SEC_CXL_GEN_MEDIA_GUID)) {
+ printk("%ssection_type: CXL General Media Error\n", newpfx);
+ /* see: cxl_cper_event_call() */
+ } else if (guid_equal(sec_type, &CPER_SEC_CXL_DRAM_GUID)) {
+ printk("%ssection_type: CXL DRAM Error\n", newpfx);
+ /* see: cxl_cper_event_call() */
+ } else if (guid_equal(sec_type, &CPER_SEC_CXL_MEM_MODULE_GUID)) {
+ printk("%ssection_type: CXL Memory Module Error\n", newpfx);
+ /* see: cxl_cper_event_call() */
} else {
const void *err = acpi_hest_get_payload(gdata);

diff --git a/include/linux/cxl-event.h b/include/linux/cxl-event.h
index 17eadee819b6..6d9a7df88d4a 100644
--- a/include/linux/cxl-event.h
+++ b/include/linux/cxl-event.h
@@ -1,12 +1,31 @@
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_CXL_EVENT_H
#define _LINUX_CXL_EVENT_H
+#include <linux/uuid.h>

/*
- * CXL event records; CXL rev 3.0
- *
- * Copyright(c) 2023 Intel Corporation.
+ * General Media Event Record
+ * CXL rev 3.0 Section 8.2.9.2.1.1; Table 8-43
+ */
+#define CPER_SEC_CXL_GEN_MEDIA_GUID \
+ GUID_INIT(0xfbcd0a77, 0xc260, 0x417f, \
+ 0x85, 0xa9, 0x08, 0x8b, 0x16, 0x21, 0xeb, 0xa6)
+
+/*
+ * DRAM Event Record
+ * CXL rev 3.0 section 8.2.9.2.1.2; Table 8-44
+ */
+#define CPER_SEC_CXL_DRAM_GUID \
+ GUID_INIT(0x601dcbb3, 0x9c06, 0x4eab, \
+ 0xb8, 0xaf, 0x4e, 0x9b, 0xfb, 0x5c, 0x96, 0x24)
+
+/*
+ * Memory Module Event Record
+ * CXL rev 3.0 section 8.2.9.2.1.3; Table 8-45
*/
+#define CPER_SEC_CXL_MEM_MODULE_GUID \
+ GUID_INIT(0xfe927475, 0xdd59, 0x4339, \
+ 0xa5, 0x86, 0x79, 0xba, 0xb1, 0x13, 0xb7, 0x74)

struct cxl_event_record_hdr {
u8 length;