Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 22e05fb5 authored by Mark Salyzyn's avatar Mark Salyzyn
Browse files

llkd: report stack signature matched 

Adjusted debugging messaging to add clarity.  Report _which_ stack
signature matched that triggered the kernel panic.  Reduce the noise
associated with missing /stack to VERBOSE as that is for development
debugging only.

Test: observe during unit test we see something like following logs:

livelock: Found SyS_openat in stack for pid XXX
livelock: S 120.000s XXX->YYY port-bridge [kill]
livelock: Killing '/vendor/bin/port-bridge' (XXX) to check forward\
          scheduling progress in S state for\
          '/vendor/bin/port-bridge' (YYY)
. . .
livelock: Found SyS_openat in stack for pid XXXXX
livelock: S 120.000s XXXXX->XXXXX llkd_unit_test [kill]
livelock: Killing '/data/nativetest64/llkd_unit_test/llkd_unit_test\
          (XXXXX) to check forward scheduling progress in S state

Test: llkd_unit_test
Bug: 33808187
Change-Id: Ifac7dd9a656208563bb20e28739abb741358d964
parent 1476931e

llkd/libllkd.cpp

+7 −3
Original line number Diff line number Diff line
@@ -737,7 +737,7 @@ bool llkCheckStack(proc* procp, const std::string& piddir) { 


    auto kernel_stack = ReadFile(piddir + "/stack");

    if (kernel_stack.empty()) {

        LOG(INFO) << piddir << "/stack empty comm=" << procp->getComm()

        LOG(VERBOSE) << piddir << "/stack empty comm=" << procp->getComm()

                     << " cmdline=" << procp->getCmdline();

        return false;

    }
@@ -745,11 +745,13 @@ bool llkCheckStack(proc* procp, const std::string& piddir) { 
    if (kernel_stack.find(" cpu_worker_pools+0x") != std::string::npos) return false;

    char idx = -1;

    char match = -1;

    std::string matched_stack_symbol = "<unknown>";

    for (const auto& stack : llkCheckStackSymbols) {

        if (++idx < 0) break;

        if ((kernel_stack.find(" "s + stack + "+0x") != std::string::npos) ||

            (kernel_stack.find(" "s + stack + ".cfi+0x") != std::string::npos)) {

            match = idx;

            matched_stack_symbol = stack;

            break;

        }

    }
@@ -760,7 +762,9 @@ bool llkCheckStack(proc* procp, const std::string& piddir) { 
    }

    if (match == char(-1)) return false;

    procp->count_stack += llkCycle;

    return procp->count_stack >= llkStateTimeoutMs[llkStateStack];

    if (procp->count_stack < llkStateTimeoutMs[llkStateStack]) return false;

    LOG(WARNING) << "Found " << matched_stack_symbol << " in stack for pid " << procp->pid;

    return true;

}

#endif