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-rw-r--r--llkd/README.md18
-rw-r--r--llkd/include/llkd.h2
-rw-r--r--llkd/libllkd.cpp3
3 files changed, 14 insertions, 9 deletions
diff --git a/llkd/README.md b/llkd/README.md
index e5be8502e..b2c5f1bb3 100644
--- a/llkd/README.md
+++ b/llkd/README.md
@@ -44,7 +44,8 @@ then have a confirmed live-lock condition and need to panic. There is no
ABA detection since forward scheduling progress is allowed, thus the condition
for the symbols are:
-- Check is looking for " " + __symbol__+ "0x" in /proc/<pid>/stack.
+- Check is looking for " __symbol__+0x" or " __symbol__.cfi+0x" in
+ /proc/__pid__/stack.
- The __symbol__ should be rare and short lived enough that on a typical
system the function is seen at most only once in a sample over the timeout
period of ro.llk.stack.timeout_ms, samples occur every ro.llk.check_ms. This
@@ -121,14 +122,14 @@ default ro.llk.timeout_ms, Z maximum timelimit.
#### ro.llk.stack.timeout_ms
default ro.llk.timeout_ms,
checking for persistent stack symbols maximum timelimit.
-Only active on userdebug and eng builds.
+Only active on userdebug or eng builds.
#### ro.llk.check_ms
default 2 minutes samples of threads for D or Z.
#### ro.llk.stack
-default cma_alloc,__get_user_pages, comma separated list of kernel symbols.
-The string "*false*" is the equivalent to an *empty* list.
+default cma_alloc,__get_user_pages,bit_wait_io comma separated list of kernel
+symbols. The string "*false*" is the equivalent to an *empty* list.
Look for kernel stack symbols that if ever persistently present can
indicate a subsystem is locked up.
Beware, check does not on purpose do forward scheduling ABA except by polling
@@ -136,11 +137,14 @@ every ro.llk_check_ms over the period ro.llk.stack.timeout_ms, so stack symbol
should be exceptionally rare and fleeting.
One must be convinced that it is virtually *impossible* for symbol to show up
persistently in all samples of the stack.
-Only active on userdebug and eng builds.
+Again, looks for a match for either " **symbol**+0x" or " **symbol**.cfi+0x"
+in stack expansion.
+Only available on userdebug or eng builds, limited privileges due to security
+concerns on user builds prevents this checking.
#### ro.llk.blacklist.process
default 0,1,2 (kernel, init and [kthreadd]) plus process names
-init,[kthreadd],[khungtaskd],lmkd,lmkd.llkd,llkd,watchdogd,
+init,[kthreadd],[khungtaskd],lmkd,llkd,watchdogd,
[watchdogd],[watchdogd/0],...,[watchdogd/***get_nprocs**-1*].
The string "*false*" is the equivalent to an *empty* list.
Do not watch these processes. A process can be comm, cmdline or pid reference.
@@ -160,7 +164,7 @@ The string "*false*" is the equivalent to an *empty* list.
Do not watch processes that match this uid.
#### ro.llk.blacklist.process.stack
-default process names init,lmkd,lmkd.llkd,llkd,keystore,logd.
+default process names init,lmkd.llkd,llkd,keystore,ueventd,apexd,logd.
The string "*false*" is the equivalent to an *empty* list.
This subset of processes are not monitored for live lock stack signatures.
Also prevents the sepolicy violation associated with processes that block
diff --git a/llkd/include/llkd.h b/llkd/include/llkd.h
index 2c62fca94..cb56f340d 100644
--- a/llkd/include/llkd.h
+++ b/llkd/include/llkd.h
@@ -48,7 +48,7 @@ unsigned llkCheckMilliseconds(void);
/* LLK_CHECK_MS_DEFAULT = actual timeout_ms / LLK_CHECKS_PER_TIMEOUT_DEFAULT */
#define LLK_CHECKS_PER_TIMEOUT_DEFAULT 5
#define LLK_CHECK_STACK_PROPERTY "ro.llk.stack"
-#define LLK_CHECK_STACK_DEFAULT "cma_alloc,__get_user_pages"
+#define LLK_CHECK_STACK_DEFAULT "cma_alloc,__get_user_pages,bit_wait_io"
#define LLK_BLACKLIST_PROCESS_PROPERTY "ro.llk.blacklist.process"
#define LLK_BLACKLIST_PROCESS_DEFAULT \
"0,1,2,init,[kthreadd],[khungtaskd],lmkd,llkd,watchdogd,[watchdogd],[watchdogd/0]"
diff --git a/llkd/libllkd.cpp b/llkd/libllkd.cpp
index 2727aab94..d92c0cd57 100644
--- a/llkd/libllkd.cpp
+++ b/llkd/libllkd.cpp
@@ -726,7 +726,8 @@ bool llkCheckStack(proc* procp, const std::string& piddir) {
char match = -1;
for (const auto& stack : llkCheckStackSymbols) {
if (++idx < 0) break;
- if (kernel_stack.find(" "s + stack + "+0x") != std::string::npos) {
+ if ((kernel_stack.find(" "s + stack + "+0x") != std::string::npos) ||
+ (kernel_stack.find(" "s + stack + ".cfi+0x") != std::string::npos)) {
match = idx;
break;
}