From: Peter Zijlstra <peterz@infradead.org>
To: x86@kernel.org
Cc: peterz@infradead.org, linux-kernel@vger.kernel.org,
rostedt@goodmis.org, mhiramat@kernel.org, bristot@redhat.com,
jbaron@akamai.com, torvalds@linux-foundation.org,
tglx@linutronix.de, mingo@kernel.org, namit@vmware.com,
hpa@zytor.com, luto@kernel.org, ard.biesheuvel@linaro.org,
jpoimboe@redhat.com, pbonzini@redhat.com,
mathieu.desnoyers@efficios.com, linux@rasmusvillemoes.dk
Subject: [PATCH v6 04/17] jump_label,module: Fix module lifetime for __jump_label_mod_text_reserved
Date: Fri, 10 Jul 2020 15:38:35 +0200 [thread overview]
Message-ID: <20200710134336.380692290@infradead.org> (raw)
In-Reply-To: 20200710133831.943894387@infradead.org
Nothing ensures the module exists while we're iterating
mod->jump_entries in __jump_label_mod_text_reserved(), take a module
reference to ensure the module sticks around.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
kernel/jump_label.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -539,19 +539,25 @@ static void static_key_set_mod(struct st
static int __jump_label_mod_text_reserved(void *start, void *end)
{
struct module *mod;
+ int ret;
preempt_disable();
mod = __module_text_address((unsigned long)start);
WARN_ON_ONCE(__module_text_address((unsigned long)end) != mod);
+ if (!try_module_get(mod))
+ mod = NULL;
preempt_enable();
if (!mod)
return 0;
-
- return __jump_label_text_reserved(mod->jump_entries,
+ ret = __jump_label_text_reserved(mod->jump_entries,
mod->jump_entries + mod->num_jump_entries,
start, end);
+
+ module_put(mod);
+
+ return ret;
}
static void __jump_label_mod_update(struct static_key *key)
next prev parent reply other threads:[~2020-07-10 13:44 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-10 13:38 [PATCH v6 00/17] Add static_call Peter Zijlstra
2020-07-10 13:38 ` [PATCH v6 01/17] notifier: Fix broken error handling pattern Peter Zijlstra
2020-07-10 13:38 ` [PATCH v6 02/17] module: Fix up module_notifier return values Peter Zijlstra
2020-07-10 13:38 ` [PATCH v6 03/17] module: Properly propagate MODULE_STATE_COMING failure Peter Zijlstra
2020-07-10 13:38 ` Peter Zijlstra [this message]
2020-07-10 13:38 ` [PATCH v6 05/17] compiler.h: Make __ADDRESSABLE() symbol truly unique Peter Zijlstra
2020-07-10 13:38 ` [PATCH v6 06/17] static_call: Add basic static call infrastructure Peter Zijlstra
2020-07-10 21:56 ` Steven Rostedt
2020-07-10 13:38 ` [PATCH v6 07/17] static_call: Add inline " Peter Zijlstra
2020-07-10 21:57 ` Steven Rostedt
2020-07-10 13:38 ` [PATCH v6 08/17] static_call: Avoid kprobes on inline static_call()s Peter Zijlstra
2020-07-10 22:00 ` Steven Rostedt
2020-07-11 10:30 ` Peter Zijlstra
2020-07-10 13:38 ` [PATCH v6 09/17] x86/static_call: Add out-of-line static call implementation Peter Zijlstra
2020-07-10 22:13 ` Steven Rostedt
2020-07-11 10:11 ` Peter Zijlstra
2020-07-10 13:38 ` [PATCH v6 10/17] x86/static_call: Add inline static call implementation for x86-64 Peter Zijlstra
2020-07-10 22:31 ` Steven Rostedt
2020-07-11 9:56 ` Peter Zijlstra
2020-07-10 13:38 ` [PATCH v6 11/17] static_call: Simple self-test Peter Zijlstra
2020-07-10 22:42 ` Steven Rostedt
2020-07-11 10:27 ` Peter Zijlstra
2020-07-13 20:26 ` Steven Rostedt
2020-07-10 13:38 ` [PATCH v6 12/17] x86/alternatives: Teach text_poke_bp() to emulate RET Peter Zijlstra
2020-07-10 22:44 ` Steven Rostedt
2020-07-10 13:38 ` [PATCH v6 13/17] static_call: Add static_call_cond() Peter Zijlstra
2020-07-10 23:08 ` Steven Rostedt
2020-07-11 5:09 ` Peter Zijlstra
2020-07-11 10:49 ` Peter Zijlstra
2020-07-13 20:32 ` Steven Rostedt
2020-07-14 9:53 ` Peter Zijlstra
2020-07-10 13:38 ` [PATCH v6 14/17] static_call: Handle tail-calls Peter Zijlstra
2020-07-11 0:23 ` Steven Rostedt
2020-07-11 5:06 ` Peter Zijlstra
2020-07-11 5:08 ` Peter Zijlstra
2020-07-10 13:38 ` [PATCH v6 15/17] static_call: Allow early init Peter Zijlstra
2020-07-11 1:14 ` Steven Rostedt
2020-07-11 5:08 ` Peter Zijlstra
2020-07-13 20:24 ` Steven Rostedt
2020-07-14 9:51 ` Peter Zijlstra
2020-07-14 14:16 ` Steven Rostedt
2020-07-14 15:54 ` Peter Zijlstra
2020-07-14 16:07 ` Steven Rostedt
2020-07-14 18:31 ` Peter Zijlstra
2020-07-14 19:38 ` Steven Rostedt
2020-07-10 13:38 ` [PATCH v6 16/17] tracepoint: Optimize using static_call() Peter Zijlstra
2020-07-10 13:38 ` [PATCH v6 17/17] x86/perf, static_call: Optimize x86_pmu methods Peter Zijlstra
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