This is a note to let you know that I've just added the patch titled static_call: Fix static_call_update() sanity check to the 5.11-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: static_call-fix-static_call_update-sanity-check.patch and it can be found in the queue-5.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 38c93587375053c5b9ef093f4a5ea754538cba32 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Date: Thu, 18 Mar 2021 11:31:51 +0100 Subject: static_call: Fix static_call_update() sanity check From: Peter Zijlstra <peterz@xxxxxxxxxxxxx> commit 38c93587375053c5b9ef093f4a5ea754538cba32 upstream. Sites that match init_section_contains() get marked as INIT. For built-in code init_sections contains both __init and __exit text. OTOH kernel_text_address() only explicitly includes __init text (and there are no __exit text markers). Match what jump_label already does and ignore the warning for INIT sites. Also see the excellent changelog for commit: 8f35eaa5f2de ("jump_label: Don't warn on __exit jump entries") Fixes: 9183c3f9ed710 ("static_call: Add inline static call infrastructure") Reported-by: Sumit Garg <sumit.garg@xxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Acked-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx> Tested-by: Sumit Garg <sumit.garg@xxxxxxxxxx> Link: https://lkml.kernel.org/r/20210318113610.739542434@xxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- kernel/jump_label.c | 8 ++++++++ kernel/static_call.c | 11 ++++++++++- 2 files changed, 18 insertions(+), 1 deletion(-) --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -407,6 +407,14 @@ static bool jump_label_can_update(struct return false; if (!kernel_text_address(jump_entry_code(entry))) { + /* + * This skips patching built-in __exit, which + * is part of init_section_contains() but is + * not part of kernel_text_address(). + * + * Skipping built-in __exit is fine since it + * will never be executed. + */ WARN_ONCE(!jump_entry_is_init(entry), "can't patch jump_label at %pS", (void *)jump_entry_code(entry)); --- a/kernel/static_call.c +++ b/kernel/static_call.c @@ -182,7 +182,16 @@ void __static_call_update(struct static_ } if (!kernel_text_address((unsigned long)site_addr)) { - WARN_ONCE(1, "can't patch static call site at %pS", + /* + * This skips patching built-in __exit, which + * is part of init_section_contains() but is + * not part of kernel_text_address(). + * + * Skipping built-in __exit is fine since it + * will never be executed. + */ + WARN_ONCE(!static_call_is_init(site), + "can't patch static call site at %pS", site_addr); continue; } Patches currently in stable-queue which might be from peterz@xxxxxxxxxxxxx are queue-5.11/static_call-fix-static_call_update-sanity-check.patch queue-5.11/perf-x86-intel-fix-a-crash-caused-by-zero-pebs-status.patch queue-5.11/perf-x86-intel-fix-unchecked-msr-access-error-caused-by-vlbr_event.patch