Pull coccinelle update from Julia Lawall:
 "Simplify the device_attr_show semantic patch

  Also removes an unused variable warning"

* tag 'cocci-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlawall/linux:
  coccinelle: device_attr_show: Remove useless expression STR

include/linux/overflow.h includes helper macros intended for calculating
sizes of allocations. These macros prevent accidental overflow by
saturating at SIZE_MAX.

In general when calculating such sizes use of the macros is preferred. Add
a semantic patch which can detect code patterns which can be replaced by
struct_size.

Note that I set the confidence to medium because this patch doesn't make an
attempt to ensure that the relevant array is actually a flexible array. The
struct_size macro does specifically require a flexible array. In many cases
the detected code could be refactored to a flexible array, but this is not
always possible (such as if there are multiple over-allocations).

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/20230227202428.3657443-1-jacob.e.keller@intel.com
Signed-off-by: Kees Cook <keescook@chromium.org>

Add rules for finding places where str_plural() can be used. This
currently finds:
 54 files changed, 62 insertions(+), 61 deletions(-)

Co-developed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://lore.kernel.org/all/fc1b25a8-6381-47c2-831c-ab6b8201a82b@intel.com/
Signed-off-by: Kees Cook <keescook@chromium.org>

Commit ff82e84e80fc ("coccinelle: device_attr_show: simplify patch case")
simplifies the patch case, as a result, STR is no longer needed.

This also helps to fix below coccicheck warning:
> warning: rp: metavariable STR not used in the - or context code

CC: Julia Lawall <Julia.Lawall@inria.fr>
CC: Nicolas Palix <nicolas.palix@imag.fr>
CC: cocci@inria.fr
Fixes: ff82e84e80fc ("coccinelle: device_attr_show: simplify patch case")
Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>

Replacing the final expression argument by ... allows the format
string to have multiple arguments.

It also has the advantage of allowing the change to be recognized as
a change in a single statement, thus avoiding adding unneeded braces.

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>

Adapt description, warning message and MODE=patch according to the latest
Documentation/filesystems/sysfs.rst:
> show() should only use sysfs_emit() or sysfs_emit_at() when formatting
> the value to be returned to user space.

After this patch:
When MODE=report,
 $ make coccicheck COCCI=scripts/coccinelle/api/device_attr_show.cocci M=drivers/hid/hid-picolcd_core.c MODE=report
 <...snip...>
 drivers/hid/hid-picolcd_core.c:304:8-16: WARNING: please use sysfs_emit or sysfs_emit_at
 drivers/hid/hid-picolcd_core.c:259:9-17: WARNING: please use sysfs_emit or sysfs_emit_at

When MODE=patch,
 $ make coccicheck COCCI=scripts/coccinelle/api/device_attr_show.cocci M=drivers/hid/hid-picolcd_core.c MODE=patch
 <...snip...>
 diff -u -p a/drivers/hid/hid-picolcd_core.c b/drivers/hid/hid-picolcd_core.c
 --- a/drivers/hid/hid-picolcd_core.c
 +++ b/drivers/hid/hid-picolcd_core.c
 @@ -255,10 +255,12 @@ static ssize_t picolcd_operation_mode_sh
  {
         struct picolcd_data *data = dev_get_drvdata(dev);

 -       if (data->status & PICOLCD_BOOTLOADER)
 -               return snprintf(buf, PAGE_SIZE, "[bootloader] lcd\n");
 -       else
 -               return snprintf(buf, PAGE_SIZE, "bootloader [lcd]\n");
 +       if (data->status & PICOLCD_BOOTLOADER) {
 +               return sysfs_emit(buf, "[bootloader] lcd\n");
 +       }
 +       else {
 +               return sysfs_emit(buf, "bootloader [lcd]\n");
 +       }
  }

  static ssize_t picolcd_operation_mode_store(struct device *dev,
 @@ -301,7 +303,7 @@ static ssize_t picolcd_operation_mode_de
  {
         struct picolcd_data *data = dev_get_drvdata(dev);

 -       return snprintf(buf, PAGE_SIZE, "hello world\n");
 +       return sysfs_emit(buf, "hello world\n");
  }

  static ssize_t picolcd_operation_mode_delay_store(struct device *dev,

CC: Julia Lawall <Julia.Lawall@inria.fr>
CC: Nicolas Palix <nicolas.palix@imag.fr>
CC: cocci@inria.fr
Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>

Remove coccinelle's recommendation to use DEFINE_DEBUGFS_ATTRIBUTE()
instead of DEFINE_SIMPLE_ATTRIBUTE().  Regardless of whether or not the
"significant overhead" incurred by debugfs_create_file() is actually
meaningful, warnings from the script have led to a rash of low-quality
patches that have sowed confusion and consumed maintainer time for little
to no benefit.  There have been no less than four attempts to "fix" KVM,
and a quick search on lore shows that KVM is not alone.

This reverts commit 5103068eaca290f890a30aae70085fac44cecaf6.

Link: https://lore.kernel.org/all/87tu2nbnz3.fsf@mpe.ellerman.id.au
Link: https://lore.kernel.org/all/c0b98151-16b6-6d8f-1765-0f7d46682d60@redhat.com
Link: https://lkml.kernel.org/r/20230706072954.4881-1-duminjie%40vivo.com
Link: https://lore.kernel.org/all/Y2FsbufV00jbyF0B@google.com
Link: https://lore.kernel.org/all/Y2ENJJ1YiSg5oHiy@orome
Link: https://lore.kernel.org/all/7560b350e7b23786ce712118a9a504356ff1cca4.camel@kernel.org
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230726202920.507756-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

A common practice is to grep for "WARNING" or "ERROR" text in the report
output from a Coccinelle semantic patch script. So, include the text
"WARNING: " in the report output generated by the semantic patch for
desired filtering of the output. Also improves the readability of the
output. Here is an example of the old and new outputs reported:

    xyz_file.c:131:39-40: atomic_add_unless
    xyz_file.c:131:39-40: WARNING: atomic_add_unless

    xyz_file.c:196:6-25: atomic_dec_and_test variation before object free at line 208.
    xyz_file.c:196:6-25: WARNING: atomic_dec_and_test variation before object free at line 208.

Signed-off-by: Deepak R Varma <drv@mailo.com>
Acked-by: Julia Lawall <Julia.Lawall@inria.fr>

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>

The various functions contain a NULL check starting in v5.15.

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>