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author | Olof Johansson <olof@lixom.net> | 2019-12-05 13:16:58 -0800 |
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committer | Olof Johansson <olof@lixom.net> | 2019-12-05 13:18:54 -0800 |
commit | 942e6f8a8314e5550e254519dfba4ccd5170421d (patch) | |
tree | 75ec655b440fbc1c454247af38b5596dd8c78de9 /kernel/debug/debug_core.c | |
parent | ARM: pxa: Fix resource properties (diff) | |
parent | Merge tag 'armsoc-defconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc (diff) | |
download | linux-dev-942e6f8a8314e5550e254519dfba4ccd5170421d.tar.xz linux-dev-942e6f8a8314e5550e254519dfba4ccd5170421d.zip |
Merge mainline/master into arm/fixes
This brings in the mainline tree right after armsoc contents was merged
this release cycle, so that we can re-run savedefconfig, etc.
Signed-off-by: Olof Johansson <olof@lixom.net>
Diffstat (limited to 'kernel/debug/debug_core.c')
-rw-r--r-- | kernel/debug/debug_core.c | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c index f76d6f77dd5e..2b7c9b67931d 100644 --- a/kernel/debug/debug_core.c +++ b/kernel/debug/debug_core.c @@ -441,6 +441,37 @@ setundefined: return 0; } +#ifdef CONFIG_KGDB_KDB +void kdb_dump_stack_on_cpu(int cpu) +{ + if (cpu == raw_smp_processor_id() || !IS_ENABLED(CONFIG_SMP)) { + dump_stack(); + return; + } + + if (!(kgdb_info[cpu].exception_state & DCPU_IS_SLAVE)) { + kdb_printf("ERROR: Task on cpu %d didn't stop in the debugger\n", + cpu); + return; + } + + /* + * In general, architectures don't support dumping the stack of a + * "running" process that's not the current one. From the point of + * view of the Linux, kernel processes that are looping in the kgdb + * slave loop are still "running". There's also no API (that actually + * works across all architectures) that can do a stack crawl based + * on registers passed as a parameter. + * + * Solve this conundrum by asking slave CPUs to do the backtrace + * themselves. + */ + kgdb_info[cpu].exception_state |= DCPU_WANT_BT; + while (kgdb_info[cpu].exception_state & DCPU_WANT_BT) + cpu_relax(); +} +#endif + /* * Return true if there is a valid kgdb I/O module. Also if no * debugger is attached a message can be printed to the console about @@ -580,6 +611,9 @@ cpu_loop: atomic_xchg(&kgdb_active, cpu); break; } + } else if (kgdb_info[cpu].exception_state & DCPU_WANT_BT) { + dump_stack(); + kgdb_info[cpu].exception_state &= ~DCPU_WANT_BT; } else if (kgdb_info[cpu].exception_state & DCPU_IS_SLAVE) { if (!raw_spin_is_locked(&dbg_slave_lock)) goto return_normal; |