| Message ID | cover.1631112725.git.mchehab+huawei@kernel.org (mailing list archive) |
|---|---|
| Headers | show |
| Series | get_abi.pl: Check for missing symbols at the ABI specs | expand |
On Wed, Sep 08, 2021 at 04:58:47PM +0200, Mauro Carvalho Chehab wrote: > Hi Greg, > > Sometime ago, I discussed with Jonathan Cameron about providing > a way check that the ABI documentation is incomplete. > > While it would be doable to validate the ABI by searching __ATTR and > similar macros around the driver, this would probably be very complex > and would take a while to parse. > > So, I ended by implementing a new feature at scripts/get_abi.pl > which does a check on the sysfs contents of a running system: > it reads everything under /sys and reads the entire ABI from > Documentation/ABI. It then warns for symbols that weren't found, > optionally showing possible candidates that might be misdefined. > > I opted to place it on 3 patches: > > The first patch adds the basic logic. It runs really quicky (up to 2 > seconds), but it doesn't use sysfs softlinks. > > Patch 2 adds support for also parsing softlinks. It slows the logic, > with now takes ~40 seconds to run on my desktop (and ~23 > seconds on a HiKey970 ARM board). There are space there for > performance improvements, by using a more sophisticated > algorithm, at the expense of making the code harder to > understand. I ended opting to use a simple implementation > for now, as ~40 seconds sounds acceptable on my eyes. > > Patch 3 adds an optional parameter to allow filtering the results > using a regex given by the user. > > One of the problems with the current ABI definitions is that several > symbols define wildcards, on non-standard ways. The more commonly > wildcards used there are: > > <foo> > {foo} > [foo] > X > Y > Z > /.../ > > The script converts the above wildcards into (somewhat relaxed) > regexes. > > There's one place using "(some description)". This one is harder to > parse, as parenthesis are used by the parsing regexes. As this happens > only on one file, patch 4 addresses such case. > > Patch 5 to 9 fix some other ABI troubles I identified. > > In long term, perhaps the better would be to just use regex on What: > fields, as this would avoid extra heuristics at get_abi.pl, but this is > OOT from this patch, and would mean a large number of changes. This is cool stuff, thanks for doing this! I'll look at it more once 5.15-rc1 is out, thanks. greg k-h
Em Thu, 9 Sep 2021 15:51:00 +0200 Greg KH <gregkh@linuxfoundation.org> escreveu: > On Wed, Sep 08, 2021 at 04:58:47PM +0200, Mauro Carvalho Chehab wrote: > > Hi Greg, > > > > Sometime ago, I discussed with Jonathan Cameron about providing > > a way check that the ABI documentation is incomplete. > > > > While it would be doable to validate the ABI by searching __ATTR and > > similar macros around the driver, this would probably be very complex > > and would take a while to parse. > > > > So, I ended by implementing a new feature at scripts/get_abi.pl > > which does a check on the sysfs contents of a running system: > > it reads everything under /sys and reads the entire ABI from > > Documentation/ABI. It then warns for symbols that weren't found, > > optionally showing possible candidates that might be misdefined. > > > > I opted to place it on 3 patches: > > > > The first patch adds the basic logic. It runs really quicky (up to 2 > > seconds), but it doesn't use sysfs softlinks. > > > > Patch 2 adds support for also parsing softlinks. It slows the logic, > > with now takes ~40 seconds to run on my desktop (and ~23 > > seconds on a HiKey970 ARM board). There are space there for > > performance improvements, by using a more sophisticated > > algorithm, at the expense of making the code harder to > > understand. I ended opting to use a simple implementation > > for now, as ~40 seconds sounds acceptable on my eyes. > > > > Patch 3 adds an optional parameter to allow filtering the results > > using a regex given by the user. > > > > One of the problems with the current ABI definitions is that several > > symbols define wildcards, on non-standard ways. The more commonly > > wildcards used there are: > > > > <foo> > > {foo} > > [foo] > > X > > Y > > Z > > /.../ > > > > The script converts the above wildcards into (somewhat relaxed) > > regexes. > > > > There's one place using "(some description)". This one is harder to > > parse, as parenthesis are used by the parsing regexes. As this happens > > only on one file, patch 4 addresses such case. > > > > Patch 5 to 9 fix some other ABI troubles I identified. > > > > In long term, perhaps the better would be to just use regex on What: > > fields, as this would avoid extra heuristics at get_abi.pl, but this is > > OOT from this patch, and would mean a large number of changes. > > This is cool stuff, thanks for doing this! > > I'll look at it more once 5.15-rc1 is out, thanks. FYI, there's a new version at: https://git.kernel.org/pub/scm/linux/kernel/git/mchehab/devel.git/log/?h=get_undefined In order for get_abi.pl to convert What: into regex, changes are needed on existing ABI files. One alternative would be to convert everything into regex, but that would probably mean that most ABI files would require work. In order to avoid a huge number of patches/changes, I opted to touch only the ones that aren't following the de-facto wildcard standards already found on most of the ABI files. So, I added support at get_abi.pl to consider those patterns as wildcards: /.../ * <foo> X Y Z [0-9] (and variants) The files that use something else meaning a wildcard need changes, in order to avoid ambiguity when the script decides if a character is either a wildcard or not. One of the issues there is with "N". several files use it as a wildcard, but USB sysfs parameters have several ABI nodes with an uppercase "N" letter (like bNumInterfaces and such). So, this one had to be converted too (and represents the vast majority of patches). Anyway, as the number of such patches is high, I'll submit the work on three separate series: - What: changes needed for regex conversion; - get_abi.pl updates; - Some additions for missing symbols found on my desktop. Thanks, Mauro
Hi Greg, Sometime ago, I discussed with Jonathan Cameron about providing a way check that the ABI documentation is incomplete. While it would be doable to validate the ABI by searching __ATTR and similar macros around the driver, this would probably be very complex and would take a while to parse. So, I ended by implementing a new feature at scripts/get_abi.pl which does a check on the sysfs contents of a running system: it reads everything under /sys and reads the entire ABI from Documentation/ABI. It then warns for symbols that weren't found, optionally showing possible candidates that might be misdefined. I opted to place it on 3 patches: The first patch adds the basic logic. It runs really quicky (up to 2 seconds), but it doesn't use sysfs softlinks. Patch 2 adds support for also parsing softlinks. It slows the logic, with now takes ~40 seconds to run on my desktop (and ~23 seconds on a HiKey970 ARM board). There are space there for performance improvements, by using a more sophisticated algorithm, at the expense of making the code harder to understand. I ended opting to use a simple implementation for now, as ~40 seconds sounds acceptable on my eyes. Patch 3 adds an optional parameter to allow filtering the results using a regex given by the user. One of the problems with the current ABI definitions is that several symbols define wildcards, on non-standard ways. The more commonly wildcards used there are: <foo> {foo} [foo] X Y Z /.../ The script converts the above wildcards into (somewhat relaxed) regexes. There's one place using "(some description)". This one is harder to parse, as parenthesis are used by the parsing regexes. As this happens only on one file, patch 4 addresses such case. Patch 5 to 9 fix some other ABI troubles I identified. In long term, perhaps the better would be to just use regex on What: fields, as this would avoid extra heuristics at get_abi.pl, but this is OOT from this patch, and would mean a large number of changes. - As reference, I sent an early implementation of this change as a RFC: https://lore.kernel.org/lkml/cover.1624014140.git.mchehab+huawei@kernel.org/ Mauro Carvalho Chehab (9): scripts: get_abi.pl: Check for missing symbols at the ABI specs scripts: get_abi.pl: detect softlinks scripts: get_abi.pl: add an option to filter undefined results ABI: sysfs-bus-usb: better document variable argument ABI: sysfs-module: better document module name parameter ABI: sysfs-tty: better document module name parameter ABI: sysfs-kernel-slab: use a wildcard for the cache name ABI: security: fix location for evm and ima_policy ABI: sysfs-module: document initstate Documentation/ABI/stable/sysfs-module | 10 +- Documentation/ABI/testing/evm | 4 +- Documentation/ABI/testing/ima_policy | 2 +- Documentation/ABI/testing/sysfs-bus-usb | 16 +- Documentation/ABI/testing/sysfs-kernel-slab | 94 ++++----- Documentation/ABI/testing/sysfs-module | 7 + Documentation/ABI/testing/sysfs-tty | 32 +-- scripts/get_abi.pl | 218 +++++++++++++++++++- 8 files changed, 303 insertions(+), 80 deletions(-)