diff options
Diffstat (limited to '0001-redhat-rh_kabi-add-a-comment-with-warning-about-RH_K.patch')
| -rw-r--r-- | 0001-redhat-rh_kabi-add-a-comment-with-warning-about-RH_K.patch | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/0001-redhat-rh_kabi-add-a-comment-with-warning-about-RH_K.patch b/0001-redhat-rh_kabi-add-a-comment-with-warning-about-RH_K.patch new file mode 100644 index 000000000..918c9877a --- /dev/null +++ b/0001-redhat-rh_kabi-add-a-comment-with-warning-about-RH_K.patch @@ -0,0 +1,67 @@ +From 597e056b1c23adf4dfc44cb725d1ab30ea227a5c Mon Sep 17 00:00:00 2001 +From: Jiri Benc <jbenc@redhat.com> +Date: Wed, 19 Feb 2020 11:52:20 +0100 +Subject: [PATCH] redhat: rh_kabi add a comment with warning about + RH_KABI_EXCLUDE usage + +RH-Acked-by: Prarit Bhargava <prarit@redhat.com> +RH-Acked-by: Don Zickus <dzickus@redhat.com> + +Upstream status: RHEL only + +We've seen attempts of incorrect RH_KABI_EXCLUDE usage. The macro is +dangerous and any structure marked by it becomes fragile. It completely +mutes the kABI checker and a future attempt to whitelist anything using +a structure annotated by RH_KABI_EXCLUDE will generate easily broken, error +prone code. Also, it bypasses module loading checks for the structure and +can lead to kernel crashes triggered by 3rd party modules unless carefully +prevented by RH_KABI_FORCE_CHANGE. + +As such, it should not be used routinely. The only valid usage is a code +heavily in flux upstream that is going to be refactored and turned upside +down, which is indirectly whitelisted and which we expect to need +backported. + +Any usage of this macro requires deep understanding of how kABI works. + +Add a big fat warning to stop the misuse. + +Upstream Status: RHEL only +Signed-off-by: Jiri Benc <jbenc@redhat.com> +--- + include/linux/rh_kabi.h | 11 ++++++++++- + 1 file changed, 10 insertions(+), 1 deletion(-) + +diff --git a/include/linux/rh_kabi.h b/include/linux/rh_kabi.h +index 4debb7aaad48..b90601e8a657 100644 +--- a/include/linux/rh_kabi.h ++++ b/include/linux/rh_kabi.h +@@ -2,7 +2,7 @@ + * rh_kabi.h - Red Hat kABI abstraction header + * + * Copyright (c) 2014 Don Zickus +- * Copyright (c) 2015-2017 Jiri Benc ++ * Copyright (c) 2015-2018 Jiri Benc + * Copyright (c) 2015 Sabrina Dubroca, Hannes Frederic Sowa + * Copyright (c) 2016-2018 Prarit Bhargava + * Copyright (c) 2017 Paolo Abeni, Larry Woodman +@@ -93,7 +93,16 @@ + * corrupt memory. Instead, by changing the symbol checksum, such modules + * won't be loaded by the kernel. This macro should only be used as a + * last resort when all other KABI workarounds have failed. ++ * + * RH_KABI_EXCLUDE ++ * !!! WARNING: DANGEROUS, DO NOT USE unless you are aware of all the !!! ++ * !!! implications. This should be used ONLY EXCEPTIONALLY and only !!! ++ * !!! under specific circumstances. Very likely, this macro does not !!! ++ * !!! do what you expect it to do. Note that any usage of this macro !!! ++ * !!! MUST be paired with a RH_KABI_FORCE_CHANGE annotation of !!! ++ * !!! a suitable symbol (or an equivalent safeguard) and the commit !!! ++ * !!! log MUST explain why the chosen solution is appropriate. !!! ++ * + * Exclude the element from checksum generation. Any such element is + * considered not to be part of the kABI whitelist and may be changed at + * will. Note however that it's the responsibility of the developer +-- +2.26.0 + |