livepatch: Remove not longer valid limitations from the documentation
Subsystems (2)
Petr Mladek
maintainerPATCH 1/1 livepatch: Remove not longer valid limitations from the documentation
Semantic changes are possible since the commit d83a7cb375eec21f04 ("livepatch: change to a per-task consistency model").
Also data structures can be patched since the commit 439e7271dc2b63de37 ("livepatch: introduce shadow variable API").
It is a high time we removed these limitations from the documentation.
---
I have found this when working on v12 of the atomic replace. It looks like a no-brainer and does not conflict with the patchset, so ... ;-)
Documentation/livepatch/livepatch.txt | 24 ------------------------ 1 file changed, 24 deletions(-)
Documentation/livepatch/livepatch.txt +0 -24
@@ -429,30 +429,6 @@ See Documentation/ABI/testing/sysfs-kernel-livepatch for more details. The current Livepatch implementation has several limitations: - - + The patch must not change the semantic of the patched functions. - - The current implementation guarantees only that either the old - or the new function is called. The functions are patched one - by one. It means that the patch must _not_ change the semantic - of the function. - - - + Data structures can not be patched. - - There is no support to version data structures or anyhow migrate - one structure into another. Also the simple consistency model does - not allow to switch more functions atomically. - - Once there is more complex consistency mode, it will be possible to - use some workarounds. For example, it will be possible to use a hole - for a new member because the data structure is aligned. Or it will - be possible to use an existing member for something else. - - There are no plans to add more generic support for modified structures - at the moment. - - + Only functions that can be traced could be patched. Livepatch is based on the dynamic ftrace. In particular, functions
Signature · 1 line
2.13.6
s/Remove not longer/Remove no longer/
Quoted 9 lines · Petr Mladek
Semantic changes are possible since the commit
d83a7cb375eec21f04("livepatch: change to a per-task consistency model").Also data structures can be patched since the commit
439e7271dc2b63de37("livepatch: introduce shadow variable API").It is a high time we removed these limitations from the documentation.
Signed-off-by Petr Mladek <[email protected]>
M
Josh Poimboeuf
Acked-byQuoted 8 lines · Miroslav Benes
s/Remove not longer/Remove no longer/
Quoted 3 lines · Petr Mladek
Semantic changes are possible since the commit
d83a7cb375eec21f04("livepatch: change to a per-task consistency model").
Quoted 8 lines
Quoted 6 lines
Also data structures can be patched since the commit
439e7271dc2b63de37("livepatch: introduce shadow variable API").It is a high time we removed these limitations from the documentation.
Signed-off-by Petr Mladek <[email protected]>Acked-by Miroslav Benes <[email protected]>
Signature · 1 line
Josh
Jiri Kosina
AppliedQuoted 6 lines · Petr Mladek
Semantic changes are possible since the commit
d83a7cb375eec21f04("livepatch: change to a per-task consistency model").Also data structures can be patched since the commit
439e7271dc2b63de37("livepatch: introduce shadow variable API").
Quoted 6 lines
It is a high time we removed these limitations from the documentation.
Signed-off-by Petr Mladek <[email protected]>---
I have found this when working on v12 of the atomic replace. It looks like a no-brainer and does not conflict with the patchset, so ... ;-)
Applied, thanks.
Signature · 2 lines
Jiri Kosina SUSE Labs