xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

pstore/ram: Introduce max_reason and convert dump_oops

Browse Source 
Now that pstore_register() can correctly pass max_reason to the kmesg
dump facility, introduce a new "max_reason" module parameter and
"max-reason" Device Tree field.

The "dump_oops" module parameter and "dump-oops" Device
Tree field are now considered deprecated, but are now automatically
converted to their corresponding max_reason values when present, though
the new max_reason setting has precedence.

For struct ramoops_platform_data, the "dump_oops" member is entirely
replaced by a new "max_reason" member, with the only existing user
updated in place.

Additionally remove the "reason" filter logic from ramoops_pstore_write(),
as that is not specifically needed anymore, though technically
this is a change in behavior for any ramoops users also setting the
printk.always_kmsg_dump boot param, which will cause ramoops to behave as
if max_reason was set to KMSG_DUMP_MAX.

Co-developed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Link: https://lore.kernel.org/lkml/20200515184434.8470-6-keescook@chromium.org/
Signed-off-by: Kees Cook <keescook@chromium.org>
This commit is contained in:
Kees Cook
2020-05-13 14:35:03 -07:00
parent 3524e688b8
commit 791205e3ec
4 changed files with 51 additions and 25 deletions
Download Patch File Download Diff File Expand all files Collapse all files

58
fs/pstore/ram.c
View File

@@ -58,10 +58,10 @@ module_param(mem_type, uint, 0400);
MODULE_PARM_DESC(mem_type,
"set to 1 to try to use unbuffered memory (default 0)");
static int dump_oops = 1;
module_param(dump_oops, int, 0400);
MODULE_PARM_DESC(dump_oops,
"set to 1 to dump oopses, 0 to only dump panics (default 1)");
static int ramoops_max_reason = -1;
module_param_named(max_reason, ramoops_max_reason, int, 0400);
MODULE_PARM_DESC(max_reason,
"maximum reason for kmsg dump (default 2: Oops and Panic) ");
static int ramoops_ecc;
module_param_named(ecc, ramoops_ecc, int, 0400);
@@ -70,6 +70,11 @@ MODULE_PARM_DESC(ramoops_ecc,
"ECC buffer size in bytes (1 is a special value, means 16 "
"bytes ECC)");
static int ramoops_dump_oops = -1;
module_param_named(dump_oops, ramoops_dump_oops, int, 0400);
MODULE_PARM_DESC(dump_oops,
"(deprecated: use max_reason instead) set to 1 to dump oopses & panics, 0 to only dump panics");
struct ramoops_context {
struct persistent_ram_zone **dprzs; /* Oops dump zones */
struct persistent_ram_zone *cprz; /* Console zone */
@@ -82,7 +87,6 @@ struct ramoops_context {
size_t console_size;
size_t ftrace_size;
size_t pmsg_size;
int dump_oops;
u32 flags;
struct persistent_ram_ecc_info ecc_info;
unsigned int max_dump_cnt;
@@ -336,16 +340,14 @@ static int notrace ramoops_pstore_write(struct pstore_record *record)
return -EINVAL;
/*
* Out of the various dmesg dump types, ramoops is currently designed
* to only store crash logs, rather than storing general kernel logs.
* We could filter on record->reason here if we wanted to (which
* would duplicate what happened before the "max_reason" setting
* was added), but that would defeat the purpose of a system
* changing printk.always_kmsg_dump, so instead log everything that
* the kmsg dumper sends us, since it should be doing the filtering
* based on the combination of printk.always_kmsg_dump and our
* requested "max_reason".
*/
if (record->reason != KMSG_DUMP_OOPS &&
record->reason != KMSG_DUMP_PANIC)
return -EINVAL;
/* Skip Oopes when configured to do so. */
if (record->reason == KMSG_DUMP_OOPS && !cxt->dump_oops)
return -EINVAL;
/*
* Explicitly only take the first part of any new crash.
@@ -647,7 +649,14 @@ static int ramoops_parse_dt(struct platform_device *pdev,
pdata->mem_size = resource_size(res);
pdata->mem_address = res->start;
pdata->mem_type = of_property_read_bool(of_node, "unbuffered");
pdata->dump_oops = !of_property_read_bool(of_node, "no-dump-oops");
/*
* Setting "no-dump-oops" is deprecated and will be ignored if
* "max_reason" is also specified.
*/
if (of_property_read_bool(of_node, "no-dump-oops"))
pdata->max_reason = KMSG_DUMP_PANIC;
else
pdata->max_reason = KMSG_DUMP_OOPS;
#define parse_u32(name, field, default_value) { \
ret = ramoops_parse_dt_u32(pdev, name, default_value, \
@@ -663,6 +672,7 @@ static int ramoops_parse_dt(struct platform_device *pdev,
parse_u32("pmsg-size", pdata->pmsg_size, 0);
parse_u32("ecc-size", pdata->ecc_info.ecc_size, 0);
parse_u32("flags", pdata->flags, 0);
parse_u32("max-reason", pdata->max_reason, pdata->max_reason);
#undef parse_u32
@@ -746,7 +756,6 @@ static int ramoops_probe(struct platform_device *pdev)
cxt->console_size = pdata->console_size;
cxt->ftrace_size = pdata->ftrace_size;
cxt->pmsg_size = pdata->pmsg_size;
cxt->dump_oops = pdata->dump_oops;
cxt->flags = pdata->flags;
cxt->ecc_info = pdata->ecc_info;
@@ -789,8 +798,10 @@ static int ramoops_probe(struct platform_device *pdev)
* the single region size is how to check.
*/
cxt->pstore.flags = 0;
if (cxt->max_dump_cnt)
if (cxt->max_dump_cnt) {
cxt->pstore.flags |= PSTORE_FLAGS_DMESG;
cxt->pstore.max_reason = pdata->max_reason;
}
if (cxt->console_size)
cxt->pstore.flags |= PSTORE_FLAGS_CONSOLE;
if (cxt->max_ftrace_cnt)
@@ -826,7 +837,7 @@ static int ramoops_probe(struct platform_device *pdev)
mem_size = pdata->mem_size;
mem_address = pdata->mem_address;
record_size = pdata->record_size;
dump_oops = pdata->dump_oops;
ramoops_max_reason = pdata->max_reason;
ramoops_console_size = pdata->console_size;
ramoops_pmsg_size = pdata->pmsg_size;
ramoops_ftrace_size = pdata->ftrace_size;
@@ -909,7 +920,16 @@ static void __init ramoops_register_dummy(void)
pdata.console_size = ramoops_console_size;
pdata.ftrace_size = ramoops_ftrace_size;
pdata.pmsg_size = ramoops_pmsg_size;
pdata.dump_oops = dump_oops;
/* If "max_reason" is set, its value has priority over "dump_oops". */
if (ramoops_max_reason >= 0)
pdata.max_reason = ramoops_max_reason;
/* Otherwise, if "dump_oops" is set, parse it into "max_reason". */
else if (ramoops_dump_oops != -1)
pdata.max_reason = ramoops_dump_oops ? KMSG_DUMP_OOPS
: KMSG_DUMP_PANIC;
/* And if neither are explicitly set, use the default. */
else
pdata.max_reason = KMSG_DUMP_OOPS;
pdata.flags = RAMOOPS_FLAG_FTRACE_PER_CPU;
/*