* [PATCH v11 0/8] error: auto propagated local_err part I
@ 2020-07-03 9:08 Vladimir Sementsov-Ogievskiy
2020-07-03 9:08 ` [PATCH v11 1/8] error: auto propagated local_err Vladimir Sementsov-Ogievskiy
` (7 more replies)
0 siblings, 8 replies; 16+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2020-07-03 9:08 UTC (permalink / raw)
To: qemu-devel
Cc: Kevin Wolf, vsementsov, Laszlo Ersek, qemu-block, Paul Durrant,
Philippe Mathieu-Daudé,
Christian Schoenebeck, armbru, Max Reitz, groug,
Stefano Stabellini, Gerd Hoffmann, Stefan Hajnoczi,
Anthony Perard, xen-devel, Michael Roth
Based-on: <20200702155000.3455325-1-armbru@redhat.com>
v11: (based-on "[PATCH v2 00/44] Less clumsy error checking")
01: minor rebase of documentation, keep r-bs
02: - minor comment tweaks [Markus]
- use explicit file name in MAINTAINERS instead of pattern
- add Markus's r-b
03,07,08: rabase changes, drop r-bs
v11 is available at
https://src.openvz.org/scm/~vsementsov/qemu.git #tag up-auto-local-err-partI-v11
v10 is available at
https://src.openvz.org/scm/~vsementsov/qemu.git #tag up-auto-local-err-partI-v10
In these series, there is no commit-per-subsystem script, each generated
commit is generated in separate.
Still, generating commands are very similar, and looks like
sed -n '/^<Subsystem name>$/,/^$/{s/^F: //p}' MAINTAINERS | \
xargs git ls-files | grep '\.[hc]$' | \
xargs spatch \
--sp-file scripts/coccinelle/auto-propagated-errp.cocci \
--macro-file scripts/cocci-macro-file.h \
--in-place --no-show-diff --max-width 80
Note, that in each generated commit, generation command is the only
text, indented by 8 spaces in 'git log -1' output, so, to regenerate all
commits (for example, after rebase, or change in coccinelle script), you
may use the following command:
git rebase -x "sh -c \"git show --pretty= --name-only | xargs git checkout HEAD^ -- ; git reset; git log -1 | grep '^ ' | sh\"" HEAD~6
Which will start automated interactive rebase for generated patches,
which will stop if generated patch changed
(you may do git commit --amend to apply updated generated changes).
Note:
git show --pretty= --name-only - lists files, changed in HEAD
git log -1 | grep '^ ' | sh - rerun generation command of HEAD
Check for compilation of changed .c files
git rebase -x "sh -c \"git show --pretty= --name-only | sed -n 's/\.c$/.o/p' | xargs make -j9\"" HEAD~6
Vladimir Sementsov-Ogievskiy (8):
error: auto propagated local_err
scripts: Coccinelle script to use ERRP_AUTO_PROPAGATE()
SD (Secure Card): introduce ERRP_AUTO_PROPAGATE
pflash: introduce ERRP_AUTO_PROPAGATE
fw_cfg: introduce ERRP_AUTO_PROPAGATE
virtio-9p: introduce ERRP_AUTO_PROPAGATE
nbd: introduce ERRP_AUTO_PROPAGATE
xen: introduce ERRP_AUTO_PROPAGATE
scripts/coccinelle/auto-propagated-errp.cocci | 337 ++++++++++++++++++
include/block/nbd.h | 1 +
include/qapi/error.h | 208 +++++++++--
block/nbd.c | 7 +-
hw/9pfs/9p-local.c | 12 +-
hw/9pfs/9p.c | 1 +
hw/block/dataplane/xen-block.c | 17 +-
hw/block/pflash_cfi01.c | 7 +-
hw/block/pflash_cfi02.c | 7 +-
hw/block/xen-block.c | 102 +++---
hw/nvram/fw_cfg.c | 14 +-
hw/pci-host/xen_igd_pt.c | 7 +-
hw/sd/sdhci-pci.c | 7 +-
hw/sd/sdhci.c | 21 +-
hw/sd/ssi-sd.c | 10 +-
hw/xen/xen-backend.c | 7 +-
hw/xen/xen-bus.c | 92 ++---
hw/xen/xen-host-pci-device.c | 27 +-
hw/xen/xen_pt.c | 25 +-
hw/xen/xen_pt_config_init.c | 17 +-
nbd/client.c | 5 +
nbd/server.c | 5 +
MAINTAINERS | 1 +
23 files changed, 690 insertions(+), 247 deletions(-)
create mode 100644 scripts/coccinelle/auto-propagated-errp.cocci
Cc: Eric Blake <eblake@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Max Reitz <mreitz@redhat.com>
Cc: Greg Kurz <groug@kaod.org>
Cc: Christian Schoenebeck <qemu_oss@crudebyte.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Anthony Perard <anthony.perard@citrix.com>
Cc: Paul Durrant <paul@xen.org>
Cc: "Philippe Mathieu-Daudé" <philmd@redhat.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Michael Roth <mdroth@linux.vnet.ibm.com>
Cc: qemu-devel@nongnu.org
Cc: qemu-block@nongnu.org
Cc: xen-devel@lists.xenproject.org
--
2.21.0
^ permalink raw reply [flat|nested] 16+ messages in thread
* [PATCH v11 1/8] error: auto propagated local_err
2020-07-03 9:08 [PATCH v11 0/8] error: auto propagated local_err part I Vladimir Sementsov-Ogievskiy
@ 2020-07-03 9:08 ` Vladimir Sementsov-Ogievskiy
2020-07-06 5:59 ` Markus Armbruster
2020-07-03 9:08 ` [PATCH v11 2/8] scripts: Coccinelle script to use ERRP_AUTO_PROPAGATE() Vladimir Sementsov-Ogievskiy
` (6 subsequent siblings)
7 siblings, 1 reply; 16+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2020-07-03 9:08 UTC (permalink / raw)
To: qemu-devel
Cc: Kevin Wolf, vsementsov, Laszlo Ersek, qemu-block, Paul Durrant,
Philippe Mathieu-Daudé,
Christian Schoenebeck, armbru, groug, Stefano Stabellini,
Gerd Hoffmann, Stefan Hajnoczi, Anthony Perard, xen-devel,
Max Reitz, Michael Roth
Introduce a new ERRP_AUTO_PROPAGATE macro, to be used at start of
functions with an errp OUT parameter.
It has three goals:
1. Fix issue with error_fatal and error_prepend/error_append_hint: user
can't see this additional information, because exit() happens in
error_setg earlier than information is added. [Reported by Greg Kurz]
2. Fix issue with error_abort and error_propagate: when we wrap
error_abort by local_err+error_propagate, the resulting coredump will
refer to error_propagate and not to the place where error happened.
(the macro itself doesn't fix the issue, but it allows us to [3.] drop
the local_err+error_propagate pattern, which will definitely fix the
issue) [Reported by Kevin Wolf]
3. Drop local_err+error_propagate pattern, which is used to workaround
void functions with errp parameter, when caller wants to know resulting
status. (Note: actually these functions could be merely updated to
return int error code).
To achieve these goals, later patches will add invocations
of this macro at the start of functions with either use
error_prepend/error_append_hint (solving 1) or which use
local_err+error_propagate to check errors, switching those
functions to use *errp instead (solving 2 and 3).
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
---
Cc: Eric Blake <eblake@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Max Reitz <mreitz@redhat.com>
Cc: Greg Kurz <groug@kaod.org>
Cc: Christian Schoenebeck <qemu_oss@crudebyte.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Anthony Perard <anthony.perard@citrix.com>
Cc: Paul Durrant <paul@xen.org>
Cc: "Philippe Mathieu-Daudé" <philmd@redhat.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Michael Roth <mdroth@linux.vnet.ibm.com>
Cc: qemu-devel@nongnu.org
Cc: qemu-block@nongnu.org
Cc: xen-devel@lists.xenproject.org
include/qapi/error.h | 205 ++++++++++++++++++++++++++++++++++++-------
1 file changed, 172 insertions(+), 33 deletions(-)
diff --git a/include/qapi/error.h b/include/qapi/error.h
index 5ceb3ace06..b54aedbfd7 100644
--- a/include/qapi/error.h
+++ b/include/qapi/error.h
@@ -39,7 +39,7 @@
* • pointer-valued functions return non-null / null pointer, and
* • integer-valued functions return non-negative / negative.
*
- * How to:
+ * = Deal with Error object =
*
* Create an error:
* error_setg(errp, "situation normal, all fouled up");
@@ -73,28 +73,91 @@
* reporting it (primarily useful in testsuites):
* error_free_or_abort(&err);
*
- * Pass an existing error to the caller:
- * error_propagate(errp, err);
- * where Error **errp is a parameter, by convention the last one.
+ * = Deal with Error ** function parameter =
*
- * Pass an existing error to the caller with the message modified:
- * error_propagate_prepend(errp, err);
+ * A function may use the error system to return errors. In this case, the
+ * function defines an Error **errp parameter, by convention the last one (with
+ * exceptions for functions using ... or va_list).
*
- * Avoid
- * error_propagate(errp, err);
- * error_prepend(errp, "Could not frobnicate '%s': ", name);
- * because this fails to prepend when @errp is &error_fatal.
+ * The caller may then pass in the following errp values:
+ *
+ * 1. &error_abort
+ * Any error will result in abort().
+ * 2. &error_fatal
+ * Any error will result in exit() with a non-zero status.
+ * 3. NULL
+ * No error reporting through errp parameter.
+ * 4. The address of a NULL-initialized Error *err
+ * Any error will populate errp with an error object.
*
- * Create a new error and pass it to the caller:
+ * The following rules then implement the correct semantics desired by the
+ * caller.
+ *
+ * Create a new error to pass to the caller:
* error_setg(errp, "situation normal, all fouled up");
*
- * Call a function and receive an error from it:
+ * Calling another errp-based function:
+ * f(..., errp);
+ *
+ * == Checking success of subcall ==
+ *
+ * If a function returns a value indicating an error in addition to setting
+ * errp (which is recommended), then you don't need any additional code, just
+ * do:
+ *
+ * int ret = f(..., errp);
+ * if (ret < 0) {
+ * ... handle error ...
+ * return ret;
+ * }
+ *
+ * If a function returns nothing (not recommended for new code), the only way
+ * to check success is by consulting errp; doing this safely requires the use
+ * of the ERRP_AUTO_PROPAGATE macro, like this:
+ *
+ * int our_func(..., Error **errp) {
+ * ERRP_AUTO_PROPAGATE();
+ * ...
+ * subcall(..., errp);
+ * if (*errp) {
+ * ...
+ * return -EINVAL;
+ * }
+ * ...
+ * }
+ *
+ * ERRP_AUTO_PROPAGATE takes care of wrapping the original errp as needed, so
+ * that the rest of the function can directly use errp (including
+ * dereferencing), where any errors will then be propagated on to the original
+ * errp when leaving the function.
+ *
+ * In some cases, we need to check result of subcall, but do not want to
+ * propagate the Error object to our caller. In such cases we don't need
+ * ERRP_AUTO_PROPAGATE, but just a local Error object:
+ *
+ * Receive an error and not pass it:
* Error *err = NULL;
- * foo(arg, &err);
+ * subcall(arg, &err);
* if (err) {
* handle the error...
+ * error_free(err);
* }
*
+ * Note that older code that did not use ERRP_AUTO_PROPAGATE would instead need
+ * a local Error * variable and the use of error_propagate() to properly handle
+ * all possible caller values of errp. Now this is DEPRECATED* (see below).
+ *
+ * Note that any function that wants to modify an error object, such as by
+ * calling error_append_hint or error_prepend, must use ERRP_AUTO_PROPAGATE, in
+ * order for a caller's use of &error_fatal to see the additional information.
+ *
+ * In rare cases, we need to pass existing Error object to the caller by hand:
+ * error_propagate(errp, err);
+ *
+ * Pass an existing error to the caller with the message modified:
+ * error_propagate_prepend(errp, err);
+ *
+ *
* Call a function ignoring errors:
* foo(arg, NULL);
*
@@ -104,26 +167,6 @@
* Call a function treating errors as fatal:
* foo(arg, &error_fatal);
*
- * Receive an error and pass it on to the caller:
- * Error *err = NULL;
- * foo(arg, &err);
- * if (err) {
- * handle the error...
- * error_propagate(errp, err);
- * }
- * where Error **errp is a parameter, by convention the last one.
- *
- * Do *not* "optimize" this to
- * foo(arg, errp);
- * if (*errp) { // WRONG!
- * handle the error...
- * }
- * because errp may be NULL!
- *
- * But when all you do with the error is pass it on, please use
- * foo(arg, errp);
- * for readability.
- *
* Receive and accumulate multiple errors (first one wins):
* Error *err = NULL, *local_err = NULL;
* foo(arg, &err);
@@ -151,6 +194,61 @@
* error_setg(&err, ...); // WRONG!
* }
* because this may pass a non-null err to error_setg().
+ *
+ * DEPRECATED*
+ *
+ * The following pattern of receiving, checking, and then forwarding an error
+ * to the caller by hand is now deprecated:
+ *
+ * Error *err = NULL;
+ * foo(arg, &err);
+ * if (err) {
+ * handle the error...
+ * error_propagate(errp, err);
+ * }
+ *
+ * Instead, use ERRP_AUTO_PROPAGATE macro.
+ *
+ * The old pattern is deprecated because of two things:
+ *
+ * 1. Issue with error_abort and error_propagate: when we wrap error_abort by
+ * local_err+error_propagate, the resulting coredump will refer to
+ * error_propagate and not to the place where error happened.
+ *
+ * 2. A lot of extra code of the same pattern
+ *
+ * How to update old code to use ERRP_AUTO_PROPAGATE?
+ *
+ * All you need is to add ERRP_AUTO_PROPAGATE() invocation at function start,
+ * than you may safely dereference errp to check errors and do not need any
+ * additional local Error variables or calls to error_propagate().
+ *
+ * Example:
+ *
+ * old code
+ *
+ * void fn(..., Error **errp) {
+ * Error *err = NULL;
+ * foo(arg, &err);
+ * if (err) {
+ * handle the error...
+ * error_propagate(errp, err);
+ * return;
+ * }
+ * ...
+ * }
+ *
+ * updated code
+ *
+ * void fn(..., Error **errp) {
+ * ERRP_AUTO_PROPAGATE();
+ * foo(arg, errp);
+ * if (*errp) {
+ * handle the error...
+ * return;
+ * }
+ * ...
+ * }
*/
#ifndef ERROR_H
@@ -359,6 +457,47 @@ void error_set_internal(Error **errp,
ErrorClass err_class, const char *fmt, ...)
GCC_FMT_ATTR(6, 7);
+typedef struct ErrorPropagator {
+ Error *local_err;
+ Error **errp;
+} ErrorPropagator;
+
+static inline void error_propagator_cleanup(ErrorPropagator *prop)
+{
+ error_propagate(prop->errp, prop->local_err);
+}
+
+G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC(ErrorPropagator, error_propagator_cleanup);
+
+/*
+ * ERRP_AUTO_PROPAGATE
+ *
+ * This macro exists to assist with proper error handling in a function which
+ * uses an Error **errp parameter. It must be used as the first line of a
+ * function which modifies an error (with error_prepend, error_append_hint, or
+ * similar) or which wants to dereference *errp. It is still safe (but
+ * useless) to use in other functions.
+ *
+ * If errp is NULL or points to error_fatal, it is rewritten to point to a
+ * local Error object, which will be automatically propagated to the original
+ * errp on function exit (see error_propagator_cleanup).
+ *
+ * After invocation of this macro it is always safe to dereference errp
+ * (as it's not NULL anymore) and to add information by error_prepend or
+ * error_append_hint (as, if it was error_fatal, we swapped it with a
+ * local_error to be propagated on cleanup).
+ *
+ * Note: we don't wrap the error_abort case, as we want resulting coredump
+ * to point to the place where the error happened, not to error_propagate.
+ */
+#define ERRP_AUTO_PROPAGATE() \
+ g_auto(ErrorPropagator) _auto_errp_prop = {.errp = errp}; \
+ do { \
+ if (!errp || errp == &error_fatal) { \
+ errp = &_auto_errp_prop.local_err; \
+ } \
+ } while (0)
+
/*
* Special error destination to abort on error.
* See error_setg() and error_propagate() for details.
--
2.21.0
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v11 2/8] scripts: Coccinelle script to use ERRP_AUTO_PROPAGATE()
2020-07-03 9:08 [PATCH v11 0/8] error: auto propagated local_err part I Vladimir Sementsov-Ogievskiy
2020-07-03 9:08 ` [PATCH v11 1/8] error: auto propagated local_err Vladimir Sementsov-Ogievskiy
@ 2020-07-03 9:08 ` Vladimir Sementsov-Ogievskiy
2020-07-03 9:08 ` [PATCH v11 3/8] SD (Secure Card): introduce ERRP_AUTO_PROPAGATE Vladimir Sementsov-Ogievskiy
` (5 subsequent siblings)
7 siblings, 0 replies; 16+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2020-07-03 9:08 UTC (permalink / raw)
To: qemu-devel
Cc: Kevin Wolf, vsementsov, Laszlo Ersek, qemu-block, Paul Durrant,
Philippe Mathieu-Daudé,
Christian Schoenebeck, armbru, Max Reitz, groug,
Stefano Stabellini, Gerd Hoffmann, Stefan Hajnoczi,
Anthony Perard, xen-devel, Michael Roth
Script adds ERRP_AUTO_PROPAGATE macro invocation where appropriate and
does corresponding changes in code (look for details in
include/qapi/error.h)
Usage example:
spatch --sp-file scripts/coccinelle/auto-propagated-errp.cocci \
--macro-file scripts/cocci-macro-file.h --in-place --no-show-diff \
--max-width 80 FILES...
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
---
Cc: Eric Blake <eblake@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Max Reitz <mreitz@redhat.com>
Cc: Greg Kurz <groug@kaod.org>
Cc: Christian Schoenebeck <qemu_oss@crudebyte.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Anthony Perard <anthony.perard@citrix.com>
Cc: Paul Durrant <paul@xen.org>
Cc: "Philippe Mathieu-Daudé" <philmd@redhat.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Michael Roth <mdroth@linux.vnet.ibm.com>
Cc: qemu-devel@nongnu.org
Cc: qemu-block@nongnu.org
Cc: xen-devel@lists.xenproject.org
scripts/coccinelle/auto-propagated-errp.cocci | 337 ++++++++++++++++++
include/qapi/error.h | 3 +
MAINTAINERS | 1 +
3 files changed, 341 insertions(+)
create mode 100644 scripts/coccinelle/auto-propagated-errp.cocci
diff --git a/scripts/coccinelle/auto-propagated-errp.cocci b/scripts/coccinelle/auto-propagated-errp.cocci
new file mode 100644
index 0000000000..c29f695adf
--- /dev/null
+++ b/scripts/coccinelle/auto-propagated-errp.cocci
@@ -0,0 +1,337 @@
+// Use ERRP_AUTO_PROPAGATE (see include/qapi/error.h)
+//
+// Copyright (c) 2020 Virtuozzo International GmbH.
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License as
+// published by the Free Software Foundation; either version 2 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see
+// <http://www.gnu.org/licenses/>.
+//
+// Usage example:
+// spatch --sp-file scripts/coccinelle/auto-propagated-errp.cocci \
+// --macro-file scripts/cocci-macro-file.h --in-place \
+// --no-show-diff --max-width 80 FILES...
+//
+// Note: --max-width 80 is needed because coccinelle default is less
+// than 80, and without this parameter coccinelle may reindent some
+// lines which fit into 80 characters but not to coccinelle default,
+// which in turn produces extra patch hunks for no reason.
+
+// Switch unusual Error ** parameter names to errp
+// (this is necessary to use ERRP_AUTO_PROPAGATE).
+//
+// Disable optional_qualifier to skip functions with
+// "Error *const *errp" parameter.
+//
+// Skip functions with "assert(_errp && *_errp)" statement, because
+// that signals unusual semantics, and the parameter name may well
+// serve a purpose. (like nbd_iter_channel_error()).
+//
+// Skip util/error.c to not touch, for example, error_propagate() and
+// error_propagate_prepend().
+@ depends on !(file in "util/error.c") disable optional_qualifier@
+identifier fn;
+identifier _errp != errp;
+@@
+
+ fn(...,
+- Error **_errp
++ Error **errp
+ ,...)
+ {
+(
+ ... when != assert(_errp && *_errp)
+&
+ <...
+- _errp
++ errp
+ ...>
+)
+ }
+
+// Add invocation of ERRP_AUTO_PROPAGATE to errp-functions where
+// necessary
+//
+// Note, that without "when any" the final "..." does not mach
+// something matched by previous pattern, i.e. the rule will not match
+// double error_prepend in control flow like in
+// vfio_set_irq_signaling().
+//
+// Note, "exists" says that we want apply rule even if it does not
+// match on all possible control flows (otherwise, it will not match
+// standard pattern when error_propagate() call is in if branch).
+@ disable optional_qualifier exists@
+identifier fn, local_err;
+symbol errp;
+@@
+
+ fn(..., Error **errp, ...)
+ {
++ ERRP_AUTO_PROPAGATE();
+ ... when != ERRP_AUTO_PROPAGATE();
+(
+(
+ error_append_hint(errp, ...);
+|
+ error_prepend(errp, ...);
+|
+ error_vprepend(errp, ...);
+)
+ ... when any
+|
+ Error *local_err = NULL;
+ ...
+(
+ error_propagate_prepend(errp, local_err, ...);
+|
+ error_propagate(errp, local_err);
+)
+ ...
+)
+ }
+
+// Warn when several Error * definitions are in the control flow.
+// This rule is not chained to rule1 and less restrictive, to cover more
+// functions to warn (even those we are not going to convert).
+//
+// Note, that even with one (or zero) Error * definition in the each
+// control flow we may have several (in total) Error * definitions in
+// the function. This case deserves attention too, but I don't see
+// simple way to match with help of coccinelle.
+@check1 disable optional_qualifier exists@
+identifier fn, _errp, local_err, local_err2;
+position p1, p2;
+@@
+
+ fn(..., Error **_errp, ...)
+ {
+ ...
+ Error *local_err = NULL;@p1
+ ... when any
+ Error *local_err2 = NULL;@p2
+ ... when any
+ }
+
+@ script:python @
+fn << check1.fn;
+p1 << check1.p1;
+p2 << check1.p2;
+@@
+
+print('Warning: function {} has several definitions of '
+ 'Error * local variable: at {}:{} and then at {}:{}'.format(
+ fn, p1[0].file, p1[0].line, p2[0].file, p2[0].line))
+
+// Warn when several propagations are in the control flow.
+@check2 disable optional_qualifier exists@
+identifier fn, _errp;
+position p1, p2;
+@@
+
+ fn(..., Error **_errp, ...)
+ {
+ ...
+(
+ error_propagate_prepend(_errp, ...);@p1
+|
+ error_propagate(_errp, ...);@p1
+)
+ ...
+(
+ error_propagate_prepend(_errp, ...);@p2
+|
+ error_propagate(_errp, ...);@p2
+)
+ ... when any
+ }
+
+@ script:python @
+fn << check2.fn;
+p1 << check2.p1;
+p2 << check2.p2;
+@@
+
+print('Warning: function {} propagates to errp several times in '
+ 'one control flow: at {}:{} and then at {}:{}'.format(
+ fn, p1[0].file, p1[0].line, p2[0].file, p2[0].line))
+
+// Match functions with propagation of local error to errp.
+// We want to refer these functions in several following rules, but I
+// don't know a proper way to inherit a function, not just its name
+// (to not match another functions with same name in following rules).
+// Not-proper way is as follows: rename errp parameter in functions
+// header and match it in following rules. Rename it back after all
+// transformations.
+//
+// The common case is a single definition of local_err with at most one
+// error_propagate_prepend() or error_propagate() on each control-flow
+// path. Functions with multiple definitions or propagates we want to
+// examine manually. Rules check1 and check2 emit warnings to guide us
+// to them.
+//
+// Note that we match not only this "common case", but any function,
+// which has the "common case" on at least one control-flow path.
+@rule1 disable optional_qualifier exists@
+identifier fn, local_err;
+symbol errp;
+@@
+
+ fn(..., Error **
+- errp
++ ____
+ , ...)
+ {
+ ...
+ Error *local_err = NULL;
+ ...
+(
+ error_propagate_prepend(errp, local_err, ...);
+|
+ error_propagate(errp, local_err);
+)
+ ...
+ }
+
+// Convert special case with goto separately.
+// I tried merging this into the following rule the obvious way, but
+// it made Coccinelle hang on block.c
+//
+// Note interesting thing: if we don't do it here, and try to fixup
+// "out: }" things later after all transformations (the rule will be
+// the same, just without error_propagate() call), coccinelle fails to
+// match this "out: }".
+@ disable optional_qualifier@
+identifier rule1.fn, rule1.local_err, out;
+symbol errp;
+@@
+
+ fn(..., Error ** ____, ...)
+ {
+ <...
+- goto out;
++ return;
+ ...>
+- out:
+- error_propagate(errp, local_err);
+ }
+
+// Convert most of local_err related stuff.
+//
+// Note, that we inherit rule1.fn and rule1.local_err names, not
+// objects themselves. We may match something not related to the
+// pattern matched by rule1. For example, local_err may be defined with
+// the same name in different blocks inside one function, and in one
+// block follow the propagation pattern and in other block doesn't.
+//
+// Note also that errp-cleaning functions
+// error_free_errp
+// error_report_errp
+// error_reportf_errp
+// warn_report_errp
+// warn_reportf_errp
+// are not yet implemented. They must call corresponding Error* -
+// freeing function and then set *errp to NULL, to avoid further
+// propagation to original errp (consider ERRP_AUTO_PROPAGATE in use).
+// For example, error_free_errp may look like this:
+//
+// void error_free_errp(Error **errp)
+// {
+// error_free(*errp);
+// *errp = NULL;
+// }
+@ disable optional_qualifier exists@
+identifier rule1.fn, rule1.local_err;
+expression list args;
+symbol errp;
+@@
+
+ fn(..., Error ** ____, ...)
+ {
+ <...
+(
+- Error *local_err = NULL;
+|
+
+// Convert error clearing functions
+(
+- error_free(local_err);
++ error_free_errp(errp);
+|
+- error_report_err(local_err);
++ error_report_errp(errp);
+|
+- error_reportf_err(local_err, args);
++ error_reportf_errp(errp, args);
+|
+- warn_report_err(local_err);
++ warn_report_errp(errp);
+|
+- warn_reportf_err(local_err, args);
++ warn_reportf_errp(errp, args);
+)
+?- local_err = NULL;
+
+|
+- error_propagate_prepend(errp, local_err, args);
++ error_prepend(errp, args);
+|
+- error_propagate(errp, local_err);
+|
+- &local_err
++ errp
+)
+ ...>
+ }
+
+// Convert remaining local_err usage. For example, different kinds of
+// error checking in if conditionals. We can't merge this into
+// previous hunk, as this conflicts with other substitutions in it (at
+// least with "- local_err = NULL").
+@ disable optional_qualifier@
+identifier rule1.fn, rule1.local_err;
+symbol errp;
+@@
+
+ fn(..., Error ** ____, ...)
+ {
+ <...
+- local_err
++ *errp
+ ...>
+ }
+
+// Always use the same pattern for checking error
+@ disable optional_qualifier@
+identifier rule1.fn;
+symbol errp;
+@@
+
+ fn(..., Error ** ____, ...)
+ {
+ <...
+- *errp != NULL
++ *errp
+ ...>
+ }
+
+// Revert temporary ___ identifier.
+@ disable optional_qualifier@
+identifier rule1.fn;
+@@
+
+ fn(..., Error **
+- ____
++ errp
+ , ...)
+ {
+ ...
+ }
diff --git a/include/qapi/error.h b/include/qapi/error.h
index b54aedbfd7..514cd1f5ae 100644
--- a/include/qapi/error.h
+++ b/include/qapi/error.h
@@ -249,6 +249,9 @@
* }
* ...
* }
+ *
+ * For mass-conversion use script
+ * scripts/coccinelle/auto-propagated-errp.cocci
*/
#ifndef ERROR_H
diff --git a/MAINTAINERS b/MAINTAINERS
index dec252f38b..65ce440217 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2165,6 +2165,7 @@ F: scripts/coccinelle/error-use-after-free.cocci
F: scripts/coccinelle/error_propagate_null.cocci
F: scripts/coccinelle/remove_local_err.cocci
F: scripts/coccinelle/use-error_fatal.cocci
+F: scripts/coccinelle/auto-propagated-errp.cocci
GDB stub
M: Alex Bennée <alex.bennee@linaro.org>
--
2.21.0
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v11 3/8] SD (Secure Card): introduce ERRP_AUTO_PROPAGATE
2020-07-03 9:08 [PATCH v11 0/8] error: auto propagated local_err part I Vladimir Sementsov-Ogievskiy
2020-07-03 9:08 ` [PATCH v11 1/8] error: auto propagated local_err Vladimir Sementsov-Ogievskiy
2020-07-03 9:08 ` [PATCH v11 2/8] scripts: Coccinelle script to use ERRP_AUTO_PROPAGATE() Vladimir Sementsov-Ogievskiy
@ 2020-07-03 9:08 ` Vladimir Sementsov-Ogievskiy
2020-07-04 16:28 ` Philippe Mathieu-Daudé
2020-07-03 9:08 ` [PATCH v11 4/8] pflash: " Vladimir Sementsov-Ogievskiy
` (4 subsequent siblings)
7 siblings, 1 reply; 16+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2020-07-03 9:08 UTC (permalink / raw)
To: qemu-devel
Cc: Kevin Wolf, vsementsov, armbru, groug, Philippe Mathieu-Daudé
If we want to add some info to errp (by error_prepend() or
error_append_hint()), we must use the ERRP_AUTO_PROPAGATE macro.
Otherwise, this info will not be added when errp == &error_fatal
(the program will exit prior to the error_append_hint() or
error_prepend() call). Fix such cases.
If we want to check error after errp-function call, we need to
introduce local_err and then propagate it to errp. Instead, use
ERRP_AUTO_PROPAGATE macro, benefits are:
1. No need of explicit error_propagate call
2. No need of explicit local_err variable: use errp directly
3. ERRP_AUTO_PROPAGATE leaves errp as is if it's not NULL or
&error_fatal, this means that we don't break error_abort
(we'll abort on error_set, not on error_propagate)
This commit is generated by command
sed -n '/^SD (Secure Card)$/,/^$/{s/^F: //p}' \
MAINTAINERS | \
xargs git ls-files | grep '\.[hc]$' | \
xargs spatch \
--sp-file scripts/coccinelle/auto-propagated-errp.cocci \
--macro-file scripts/cocci-macro-file.h \
--in-place --no-show-diff --max-width 80
Reported-by: Kevin Wolf <kwolf@redhat.com>
Reported-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
hw/sd/sdhci-pci.c | 7 +++----
hw/sd/sdhci.c | 21 +++++++++------------
hw/sd/ssi-sd.c | 10 +++++-----
3 files changed, 17 insertions(+), 21 deletions(-)
diff --git a/hw/sd/sdhci-pci.c b/hw/sd/sdhci-pci.c
index 4f5977d487..38ec572fc6 100644
--- a/hw/sd/sdhci-pci.c
+++ b/hw/sd/sdhci-pci.c
@@ -29,13 +29,12 @@ static Property sdhci_pci_properties[] = {
static void sdhci_pci_realize(PCIDevice *dev, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
SDHCIState *s = PCI_SDHCI(dev);
- Error *local_err = NULL;
sdhci_initfn(s);
- sdhci_common_realize(s, &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
+ sdhci_common_realize(s, errp);
+ if (*errp) {
return;
}
diff --git a/hw/sd/sdhci.c b/hw/sd/sdhci.c
index eb2be6529e..be1928784d 100644
--- a/hw/sd/sdhci.c
+++ b/hw/sd/sdhci.c
@@ -1288,7 +1288,7 @@ static const MemoryRegionOps sdhci_mmio_ops = {
static void sdhci_init_readonly_registers(SDHCIState *s, Error **errp)
{
- Error *local_err = NULL;
+ ERRP_AUTO_PROPAGATE();
switch (s->sd_spec_version) {
case 2 ... 3:
@@ -1299,9 +1299,8 @@ static void sdhci_init_readonly_registers(SDHCIState *s, Error **errp)
}
s->version = (SDHC_HCVER_VENDOR << 8) | (s->sd_spec_version - 1);
- sdhci_check_capareg(s, &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
+ sdhci_check_capareg(s, errp);
+ if (*errp) {
return;
}
}
@@ -1332,11 +1331,10 @@ void sdhci_uninitfn(SDHCIState *s)
void sdhci_common_realize(SDHCIState *s, Error **errp)
{
- Error *local_err = NULL;
+ ERRP_AUTO_PROPAGATE();
- sdhci_init_readonly_registers(s, &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
+ sdhci_init_readonly_registers(s, errp);
+ if (*errp) {
return;
}
s->buf_maxsz = sdhci_get_fifolen(s);
@@ -1456,13 +1454,12 @@ static void sdhci_sysbus_finalize(Object *obj)
static void sdhci_sysbus_realize(DeviceState *dev, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
SDHCIState *s = SYSBUS_SDHCI(dev);
SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
- Error *local_err = NULL;
- sdhci_common_realize(s, &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
+ sdhci_common_realize(s, errp);
+ if (*errp) {
return;
}
diff --git a/hw/sd/ssi-sd.c b/hw/sd/ssi-sd.c
index e0fb9f3093..43e5730b00 100644
--- a/hw/sd/ssi-sd.c
+++ b/hw/sd/ssi-sd.c
@@ -241,10 +241,10 @@ static const VMStateDescription vmstate_ssi_sd = {
static void ssi_sd_realize(SSISlave *d, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
ssi_sd_state *s = FROM_SSI_SLAVE(ssi_sd_state, d);
DeviceState *carddev;
DriveInfo *dinfo;
- Error *err = NULL;
qbus_create_inplace(&s->sdbus, sizeof(s->sdbus), TYPE_SD_BUS,
DEVICE(d), "sd-bus");
@@ -255,23 +255,23 @@ static void ssi_sd_realize(SSISlave *d, Error **errp)
carddev = qdev_new(TYPE_SD_CARD);
if (dinfo) {
if (!qdev_prop_set_drive_err(carddev, "drive",
- blk_by_legacy_dinfo(dinfo), &err)) {
+ blk_by_legacy_dinfo(dinfo), errp)) {
goto fail;
}
}
- if (!object_property_set_bool(OBJECT(carddev), "spi", true, &err)) {
+ if (!object_property_set_bool(OBJECT(carddev), "spi", true, errp)) {
goto fail;
}
- if (!qdev_realize_and_unref(carddev, BUS(&s->sdbus), &err)) {
+ if (!qdev_realize_and_unref(carddev, BUS(&s->sdbus), errp)) {
goto fail;
}
return;
fail:
- error_propagate_prepend(errp, err, "failed to init SD card: ");
+ error_prepend(errp, "failed to init SD card: ");
}
static void ssi_sd_reset(DeviceState *dev)
--
2.21.0
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v11 4/8] pflash: introduce ERRP_AUTO_PROPAGATE
2020-07-03 9:08 [PATCH v11 0/8] error: auto propagated local_err part I Vladimir Sementsov-Ogievskiy
` (2 preceding siblings ...)
2020-07-03 9:08 ` [PATCH v11 3/8] SD (Secure Card): introduce ERRP_AUTO_PROPAGATE Vladimir Sementsov-Ogievskiy
@ 2020-07-03 9:08 ` Vladimir Sementsov-Ogievskiy
2020-07-03 9:08 ` [PATCH v11 5/8] fw_cfg: " Vladimir Sementsov-Ogievskiy
` (3 subsequent siblings)
7 siblings, 0 replies; 16+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2020-07-03 9:08 UTC (permalink / raw)
To: qemu-devel
Cc: Kevin Wolf, vsementsov, qemu-block, armbru, groug, Max Reitz,
Philippe Mathieu-Daudé
If we want to add some info to errp (by error_prepend() or
error_append_hint()), we must use the ERRP_AUTO_PROPAGATE macro.
Otherwise, this info will not be added when errp == &error_fatal
(the program will exit prior to the error_append_hint() or
error_prepend() call). Fix such cases.
If we want to check error after errp-function call, we need to
introduce local_err and then propagate it to errp. Instead, use
ERRP_AUTO_PROPAGATE macro, benefits are:
1. No need of explicit error_propagate call
2. No need of explicit local_err variable: use errp directly
3. ERRP_AUTO_PROPAGATE leaves errp as is if it's not NULL or
&error_fatal, this means that we don't break error_abort
(we'll abort on error_set, not on error_propagate)
This commit is generated by command
sed -n '/^Parallel NOR Flash devices$/,/^$/{s/^F: //p}' \
MAINTAINERS | \
xargs git ls-files | grep '\.[hc]$' | \
xargs spatch \
--sp-file scripts/coccinelle/auto-propagated-errp.cocci \
--macro-file scripts/cocci-macro-file.h \
--in-place --no-show-diff --max-width 80
Reported-by: Kevin Wolf <kwolf@redhat.com>
Reported-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
hw/block/pflash_cfi01.c | 7 +++----
hw/block/pflash_cfi02.c | 7 +++----
2 files changed, 6 insertions(+), 8 deletions(-)
diff --git a/hw/block/pflash_cfi01.c b/hw/block/pflash_cfi01.c
index cddc3a5a0c..859cfeae14 100644
--- a/hw/block/pflash_cfi01.c
+++ b/hw/block/pflash_cfi01.c
@@ -696,12 +696,12 @@ static const MemoryRegionOps pflash_cfi01_ops = {
static void pflash_cfi01_realize(DeviceState *dev, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
PFlashCFI01 *pfl = PFLASH_CFI01(dev);
uint64_t total_len;
int ret;
uint64_t blocks_per_device, sector_len_per_device, device_len;
int num_devices;
- Error *local_err = NULL;
if (pfl->sector_len == 0) {
error_setg(errp, "attribute \"sector-length\" not specified or zero.");
@@ -735,9 +735,8 @@ static void pflash_cfi01_realize(DeviceState *dev, Error **errp)
&pfl->mem, OBJECT(dev),
&pflash_cfi01_ops,
pfl,
- pfl->name, total_len, &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
+ pfl->name, total_len, errp);
+ if (*errp) {
return;
}
diff --git a/hw/block/pflash_cfi02.c b/hw/block/pflash_cfi02.c
index b40ce2335a..15035ee5ef 100644
--- a/hw/block/pflash_cfi02.c
+++ b/hw/block/pflash_cfi02.c
@@ -724,9 +724,9 @@ static const MemoryRegionOps pflash_cfi02_ops = {
static void pflash_cfi02_realize(DeviceState *dev, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
PFlashCFI02 *pfl = PFLASH_CFI02(dev);
int ret;
- Error *local_err = NULL;
if (pfl->uniform_sector_len == 0 && pfl->sector_len[0] == 0) {
error_setg(errp, "attribute \"sector-length\" not specified or zero.");
@@ -792,9 +792,8 @@ static void pflash_cfi02_realize(DeviceState *dev, Error **errp)
memory_region_init_rom_device(&pfl->orig_mem, OBJECT(pfl),
&pflash_cfi02_ops, pfl, pfl->name,
- pfl->chip_len, &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
+ pfl->chip_len, errp);
+ if (*errp) {
return;
}
--
2.21.0
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v11 5/8] fw_cfg: introduce ERRP_AUTO_PROPAGATE
2020-07-03 9:08 [PATCH v11 0/8] error: auto propagated local_err part I Vladimir Sementsov-Ogievskiy
` (3 preceding siblings ...)
2020-07-03 9:08 ` [PATCH v11 4/8] pflash: " Vladimir Sementsov-Ogievskiy
@ 2020-07-03 9:08 ` Vladimir Sementsov-Ogievskiy
2020-07-03 9:08 ` [PATCH v11 6/8] virtio-9p: " Vladimir Sementsov-Ogievskiy
` (2 subsequent siblings)
7 siblings, 0 replies; 16+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2020-07-03 9:08 UTC (permalink / raw)
To: qemu-devel
Cc: Kevin Wolf, vsementsov, Laszlo Ersek, armbru, groug,
Gerd Hoffmann, Philippe Mathieu-Daudé
If we want to add some info to errp (by error_prepend() or
error_append_hint()), we must use the ERRP_AUTO_PROPAGATE macro.
Otherwise, this info will not be added when errp == &error_fatal
(the program will exit prior to the error_append_hint() or
error_prepend() call). Fix such cases.
If we want to check error after errp-function call, we need to
introduce local_err and then propagate it to errp. Instead, use
ERRP_AUTO_PROPAGATE macro, benefits are:
1. No need of explicit error_propagate call
2. No need of explicit local_err variable: use errp directly
3. ERRP_AUTO_PROPAGATE leaves errp as is if it's not NULL or
&error_fatal, this means that we don't break error_abort
(we'll abort on error_set, not on error_propagate)
This commit is generated by command
sed -n '/^Firmware configuration (fw_cfg)$/,/^$/{s/^F: //p}' \
MAINTAINERS | \
xargs git ls-files | grep '\.[hc]$' | \
xargs spatch \
--sp-file scripts/coccinelle/auto-propagated-errp.cocci \
--macro-file scripts/cocci-macro-file.h \
--in-place --no-show-diff --max-width 80
Reported-by: Kevin Wolf <kwolf@redhat.com>
Reported-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
hw/nvram/fw_cfg.c | 14 ++++++--------
1 file changed, 6 insertions(+), 8 deletions(-)
diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c
index 0408a31f8e..d5386c3235 100644
--- a/hw/nvram/fw_cfg.c
+++ b/hw/nvram/fw_cfg.c
@@ -1231,12 +1231,11 @@ static Property fw_cfg_io_properties[] = {
static void fw_cfg_io_realize(DeviceState *dev, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
FWCfgIoState *s = FW_CFG_IO(dev);
- Error *local_err = NULL;
- fw_cfg_file_slots_allocate(FW_CFG(s), &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
+ fw_cfg_file_slots_allocate(FW_CFG(s), errp);
+ if (*errp) {
return;
}
@@ -1282,14 +1281,13 @@ static Property fw_cfg_mem_properties[] = {
static void fw_cfg_mem_realize(DeviceState *dev, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
FWCfgMemState *s = FW_CFG_MEM(dev);
SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
const MemoryRegionOps *data_ops = &fw_cfg_data_mem_ops;
- Error *local_err = NULL;
- fw_cfg_file_slots_allocate(FW_CFG(s), &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
+ fw_cfg_file_slots_allocate(FW_CFG(s), errp);
+ if (*errp) {
return;
}
--
2.21.0
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v11 6/8] virtio-9p: introduce ERRP_AUTO_PROPAGATE
2020-07-03 9:08 [PATCH v11 0/8] error: auto propagated local_err part I Vladimir Sementsov-Ogievskiy
` (4 preceding siblings ...)
2020-07-03 9:08 ` [PATCH v11 5/8] fw_cfg: " Vladimir Sementsov-Ogievskiy
@ 2020-07-03 9:08 ` Vladimir Sementsov-Ogievskiy
2020-07-03 9:08 ` [PATCH v11 7/8] nbd: " Vladimir Sementsov-Ogievskiy
2020-07-03 9:08 ` [PATCH v11 8/8] xen: " Vladimir Sementsov-Ogievskiy
7 siblings, 0 replies; 16+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2020-07-03 9:08 UTC (permalink / raw)
To: qemu-devel; +Cc: Kevin Wolf, vsementsov, Christian Schoenebeck, armbru, groug
If we want to add some info to errp (by error_prepend() or
error_append_hint()), we must use the ERRP_AUTO_PROPAGATE macro.
Otherwise, this info will not be added when errp == &error_fatal
(the program will exit prior to the error_append_hint() or
error_prepend() call). Fix such cases.
If we want to check error after errp-function call, we need to
introduce local_err and then propagate it to errp. Instead, use
ERRP_AUTO_PROPAGATE macro, benefits are:
1. No need of explicit error_propagate call
2. No need of explicit local_err variable: use errp directly
3. ERRP_AUTO_PROPAGATE leaves errp as is if it's not NULL or
&error_fatal, this means that we don't break error_abort
(we'll abort on error_set, not on error_propagate)
This commit is generated by command
sed -n '/^virtio-9p$/,/^$/{s/^F: //p}' MAINTAINERS | \
xargs git ls-files | grep '\.[hc]$' | \
xargs spatch \
--sp-file scripts/coccinelle/auto-propagated-errp.cocci \
--macro-file scripts/cocci-macro-file.h \
--in-place --no-show-diff --max-width 80
Reported-by: Kevin Wolf <kwolf@redhat.com>
Reported-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Acked-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
---
hw/9pfs/9p-local.c | 12 +++++-------
hw/9pfs/9p.c | 1 +
2 files changed, 6 insertions(+), 7 deletions(-)
diff --git a/hw/9pfs/9p-local.c b/hw/9pfs/9p-local.c
index 54e012e5b4..0361e0c0b4 100644
--- a/hw/9pfs/9p-local.c
+++ b/hw/9pfs/9p-local.c
@@ -1479,10 +1479,10 @@ static void error_append_security_model_hint(Error *const *errp)
static int local_parse_opts(QemuOpts *opts, FsDriverEntry *fse, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
const char *sec_model = qemu_opt_get(opts, "security_model");
const char *path = qemu_opt_get(opts, "path");
const char *multidevs = qemu_opt_get(opts, "multidevs");
- Error *local_err = NULL;
if (!sec_model) {
error_setg(errp, "security_model property not set");
@@ -1516,11 +1516,10 @@ static int local_parse_opts(QemuOpts *opts, FsDriverEntry *fse, Error **errp)
fse->export_flags &= ~V9FS_FORBID_MULTIDEVS;
fse->export_flags &= ~V9FS_REMAP_INODES;
} else {
- error_setg(&local_err, "invalid multidevs property '%s'",
+ error_setg(errp, "invalid multidevs property '%s'",
multidevs);
- error_append_hint(&local_err, "Valid options are: multidevs="
+ error_append_hint(errp, "Valid options are: multidevs="
"[remap|forbid|warn]\n");
- error_propagate(errp, local_err);
return -1;
}
}
@@ -1530,9 +1529,8 @@ static int local_parse_opts(QemuOpts *opts, FsDriverEntry *fse, Error **errp)
return -1;
}
- if (fsdev_throttle_parse_opts(opts, &fse->fst, &local_err)) {
- error_propagate_prepend(errp, local_err,
- "invalid throttle configuration: ");
+ if (fsdev_throttle_parse_opts(opts, &fse->fst, errp)) {
+ error_prepend(errp, "invalid throttle configuration: ");
return -1;
}
diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c
index 9755fba9a9..bdb1360482 100644
--- a/hw/9pfs/9p.c
+++ b/hw/9pfs/9p.c
@@ -4011,6 +4011,7 @@ void pdu_submit(V9fsPDU *pdu, P9MsgHeader *hdr)
int v9fs_device_realize_common(V9fsState *s, const V9fsTransport *t,
Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
int i, len;
struct stat stat;
FsDriverEntry *fse;
--
2.21.0
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v11 7/8] nbd: introduce ERRP_AUTO_PROPAGATE
2020-07-03 9:08 [PATCH v11 0/8] error: auto propagated local_err part I Vladimir Sementsov-Ogievskiy
` (5 preceding siblings ...)
2020-07-03 9:08 ` [PATCH v11 6/8] virtio-9p: " Vladimir Sementsov-Ogievskiy
@ 2020-07-03 9:08 ` Vladimir Sementsov-Ogievskiy
2020-07-06 5:22 ` Markus Armbruster
2020-07-07 11:51 ` Markus Armbruster
2020-07-03 9:08 ` [PATCH v11 8/8] xen: " Vladimir Sementsov-Ogievskiy
7 siblings, 2 replies; 16+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2020-07-03 9:08 UTC (permalink / raw)
To: qemu-devel; +Cc: Kevin Wolf, vsementsov, qemu-block, armbru, Max Reitz, groug
If we want to add some info to errp (by error_prepend() or
error_append_hint()), we must use the ERRP_AUTO_PROPAGATE macro.
Otherwise, this info will not be added when errp == &error_fatal
(the program will exit prior to the error_append_hint() or
error_prepend() call). Fix such cases.
If we want to check error after errp-function call, we need to
introduce local_err and then propagate it to errp. Instead, use
ERRP_AUTO_PROPAGATE macro, benefits are:
1. No need of explicit error_propagate call
2. No need of explicit local_err variable: use errp directly
3. ERRP_AUTO_PROPAGATE leaves errp as is if it's not NULL or
&error_fatal, this means that we don't break error_abort
(we'll abort on error_set, not on error_propagate)
This commit is generated by command
sed -n '/^Network Block Device (NBD)$/,/^$/{s/^F: //p}' \
MAINTAINERS | \
xargs git ls-files | grep '\.[hc]$' | \
xargs spatch \
--sp-file scripts/coccinelle/auto-propagated-errp.cocci \
--macro-file scripts/cocci-macro-file.h \
--in-place --no-show-diff --max-width 80
Reported-by: Kevin Wolf <kwolf@redhat.com>
Reported-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
include/block/nbd.h | 1 +
block/nbd.c | 7 +++----
nbd/client.c | 5 +++++
nbd/server.c | 5 +++++
4 files changed, 14 insertions(+), 4 deletions(-)
diff --git a/include/block/nbd.h b/include/block/nbd.h
index 20363280ae..f7d87636d3 100644
--- a/include/block/nbd.h
+++ b/include/block/nbd.h
@@ -361,6 +361,7 @@ void nbd_server_start_options(NbdServerOptions *arg, Error **errp);
static inline int nbd_read(QIOChannel *ioc, void *buffer, size_t size,
const char *desc, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
int ret = qio_channel_read_all(ioc, buffer, size, errp) < 0 ? -EIO : 0;
if (ret < 0) {
diff --git a/block/nbd.c b/block/nbd.c
index 6876da04a7..b7cea0f650 100644
--- a/block/nbd.c
+++ b/block/nbd.c
@@ -1408,16 +1408,15 @@ static void nbd_client_close(BlockDriverState *bs)
static QIOChannelSocket *nbd_establish_connection(SocketAddress *saddr,
Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
QIOChannelSocket *sioc;
- Error *local_err = NULL;
sioc = qio_channel_socket_new();
qio_channel_set_name(QIO_CHANNEL(sioc), "nbd-client");
- qio_channel_socket_connect_sync(sioc, saddr, &local_err);
- if (local_err) {
+ qio_channel_socket_connect_sync(sioc, saddr, errp);
+ if (*errp) {
object_unref(OBJECT(sioc));
- error_propagate(errp, local_err);
return NULL;
}
diff --git a/nbd/client.c b/nbd/client.c
index ba173108ba..e258ef3f7e 100644
--- a/nbd/client.c
+++ b/nbd/client.c
@@ -68,6 +68,7 @@ static int nbd_send_option_request(QIOChannel *ioc, uint32_t opt,
uint32_t len, const char *data,
Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
NBDOption req;
QEMU_BUILD_BUG_ON(sizeof(req) != 16);
@@ -153,6 +154,7 @@ static int nbd_receive_option_reply(QIOChannel *ioc, uint32_t opt,
static int nbd_handle_reply_err(QIOChannel *ioc, NBDOptionReply *reply,
bool strict, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
g_autofree char *msg = NULL;
if (!(reply->type & (1 << 31))) {
@@ -337,6 +339,7 @@ static int nbd_receive_list(QIOChannel *ioc, char **name, char **description,
static int nbd_opt_info_or_go(QIOChannel *ioc, uint32_t opt,
NBDExportInfo *info, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
NBDOptionReply reply;
uint32_t len = strlen(info->name);
uint16_t type;
@@ -882,6 +885,7 @@ static int nbd_start_negotiate(AioContext *aio_context, QIOChannel *ioc,
bool structured_reply, bool *zeroes,
Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
uint64_t magic;
trace_nbd_start_negotiate(tlscreds, hostname ? hostname : "<null>");
@@ -1017,6 +1021,7 @@ int nbd_receive_negotiate(AioContext *aio_context, QIOChannel *ioc,
const char *hostname, QIOChannel **outioc,
NBDExportInfo *info, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
int result;
bool zeroes;
bool base_allocation = info->base_allocation;
diff --git a/nbd/server.c b/nbd/server.c
index 20754e9ebc..8a12e586d7 100644
--- a/nbd/server.c
+++ b/nbd/server.c
@@ -211,6 +211,7 @@ static int GCC_FMT_ATTR(4, 0)
nbd_negotiate_send_rep_verr(NBDClient *client, uint32_t type,
Error **errp, const char *fmt, va_list va)
{
+ ERRP_AUTO_PROPAGATE();
g_autofree char *msg = NULL;
int ret;
size_t len;
@@ -382,6 +383,7 @@ static int nbd_opt_read_name(NBDClient *client, char **name, uint32_t *length,
static int nbd_negotiate_send_rep_list(NBDClient *client, NBDExport *exp,
Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
size_t name_len, desc_len;
uint32_t len;
const char *name = exp->name ? exp->name : "";
@@ -445,6 +447,7 @@ static void nbd_check_meta_export(NBDClient *client)
static int nbd_negotiate_handle_export_name(NBDClient *client, bool no_zeroes,
Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
g_autofree char *name = NULL;
char buf[NBD_REPLY_EXPORT_NAME_SIZE] = "";
size_t len;
@@ -1289,6 +1292,7 @@ static int nbd_negotiate_options(NBDClient *client, Error **errp)
*/
static coroutine_fn int nbd_negotiate(NBDClient *client, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
char buf[NBD_OLDSTYLE_NEGOTIATE_SIZE] = "";
int ret;
@@ -1663,6 +1667,7 @@ void nbd_export_close(NBDExport *exp)
void nbd_export_remove(NBDExport *exp, NbdServerRemoveMode mode, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
if (mode == NBD_SERVER_REMOVE_MODE_HARD || QTAILQ_EMPTY(&exp->clients)) {
nbd_export_close(exp);
return;
--
2.21.0
^ permalink raw reply related [flat|nested] 16+ messages in thread
* [PATCH v11 8/8] xen: introduce ERRP_AUTO_PROPAGATE
2020-07-03 9:08 [PATCH v11 0/8] error: auto propagated local_err part I Vladimir Sementsov-Ogievskiy
` (6 preceding siblings ...)
2020-07-03 9:08 ` [PATCH v11 7/8] nbd: " Vladimir Sementsov-Ogievskiy
@ 2020-07-03 9:08 ` Vladimir Sementsov-Ogievskiy
2020-07-04 16:36 ` Philippe Mathieu-Daudé
7 siblings, 1 reply; 16+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2020-07-03 9:08 UTC (permalink / raw)
To: qemu-devel
Cc: Kevin Wolf, Stefano Stabellini, qemu-block, Paul Durrant, armbru,
groug, vsementsov, Stefan Hajnoczi, Anthony Perard, xen-devel,
Max Reitz
If we want to add some info to errp (by error_prepend() or
error_append_hint()), we must use the ERRP_AUTO_PROPAGATE macro.
Otherwise, this info will not be added when errp == &error_fatal
(the program will exit prior to the error_append_hint() or
error_prepend() call). Fix such cases.
If we want to check error after errp-function call, we need to
introduce local_err and then propagate it to errp. Instead, use
ERRP_AUTO_PROPAGATE macro, benefits are:
1. No need of explicit error_propagate call
2. No need of explicit local_err variable: use errp directly
3. ERRP_AUTO_PROPAGATE leaves errp as is if it's not NULL or
&error_fatal, this means that we don't break error_abort
(we'll abort on error_set, not on error_propagate)
This commit is generated by command
sed -n '/^X86 Xen CPUs$/,/^$/{s/^F: //p}' MAINTAINERS | \
xargs git ls-files | grep '\.[hc]$' | \
xargs spatch \
--sp-file scripts/coccinelle/auto-propagated-errp.cocci \
--macro-file scripts/cocci-macro-file.h \
--in-place --no-show-diff --max-width 80
Reported-by: Kevin Wolf <kwolf@redhat.com>
Reported-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
hw/block/dataplane/xen-block.c | 17 +++---
hw/block/xen-block.c | 102 ++++++++++++++-------------------
hw/pci-host/xen_igd_pt.c | 7 +--
hw/xen/xen-backend.c | 7 +--
hw/xen/xen-bus.c | 92 +++++++++++++----------------
hw/xen/xen-host-pci-device.c | 27 +++++----
hw/xen/xen_pt.c | 25 ++++----
hw/xen/xen_pt_config_init.c | 17 +++---
8 files changed, 128 insertions(+), 166 deletions(-)
diff --git a/hw/block/dataplane/xen-block.c b/hw/block/dataplane/xen-block.c
index 5f8f15778b..1a077cc05f 100644
--- a/hw/block/dataplane/xen-block.c
+++ b/hw/block/dataplane/xen-block.c
@@ -723,8 +723,8 @@ void xen_block_dataplane_start(XenBlockDataPlane *dataplane,
unsigned int protocol,
Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
XenDevice *xendev = dataplane->xendev;
- Error *local_err = NULL;
unsigned int ring_size;
unsigned int i;
@@ -760,9 +760,8 @@ void xen_block_dataplane_start(XenBlockDataPlane *dataplane,
}
xen_device_set_max_grant_refs(xendev, dataplane->nr_ring_ref,
- &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
+ errp);
+ if (*errp) {
goto stop;
}
@@ -770,9 +769,8 @@ void xen_block_dataplane_start(XenBlockDataPlane *dataplane,
dataplane->ring_ref,
dataplane->nr_ring_ref,
PROT_READ | PROT_WRITE,
- &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
+ errp);
+ if (*errp) {
goto stop;
}
@@ -805,9 +803,8 @@ void xen_block_dataplane_start(XenBlockDataPlane *dataplane,
dataplane->event_channel =
xen_device_bind_event_channel(xendev, event_channel,
xen_block_dataplane_event, dataplane,
- &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
+ errp);
+ if (*errp) {
goto stop;
}
diff --git a/hw/block/xen-block.c b/hw/block/xen-block.c
index a775fba7c0..623ae5b8e0 100644
--- a/hw/block/xen-block.c
+++ b/hw/block/xen-block.c
@@ -195,6 +195,7 @@ static const BlockDevOps xen_block_dev_ops = {
static void xen_block_realize(XenDevice *xendev, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
XenBlockDevice *blockdev = XEN_BLOCK_DEVICE(xendev);
XenBlockDeviceClass *blockdev_class =
XEN_BLOCK_DEVICE_GET_CLASS(xendev);
@@ -202,7 +203,6 @@ static void xen_block_realize(XenDevice *xendev, Error **errp)
XenBlockVdev *vdev = &blockdev->props.vdev;
BlockConf *conf = &blockdev->props.conf;
BlockBackend *blk = conf->blk;
- Error *local_err = NULL;
if (vdev->type == XEN_BLOCK_VDEV_TYPE_INVALID) {
error_setg(errp, "vdev property not set");
@@ -212,9 +212,8 @@ static void xen_block_realize(XenDevice *xendev, Error **errp)
trace_xen_block_realize(type, vdev->disk, vdev->partition);
if (blockdev_class->realize) {
- blockdev_class->realize(blockdev, &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
+ blockdev_class->realize(blockdev, errp);
+ if (*errp) {
return;
}
}
@@ -280,8 +279,8 @@ static void xen_block_frontend_changed(XenDevice *xendev,
enum xenbus_state frontend_state,
Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
enum xenbus_state backend_state = xen_device_backend_get_state(xendev);
- Error *local_err = NULL;
switch (frontend_state) {
case XenbusStateInitialised:
@@ -290,15 +289,13 @@ static void xen_block_frontend_changed(XenDevice *xendev,
break;
}
- xen_block_disconnect(xendev, &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
+ xen_block_disconnect(xendev, errp);
+ if (*errp) {
break;
}
- xen_block_connect(xendev, &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
+ xen_block_connect(xendev, errp);
+ if (*errp) {
break;
}
@@ -311,9 +308,8 @@ static void xen_block_frontend_changed(XenDevice *xendev,
case XenbusStateClosed:
case XenbusStateUnknown:
- xen_block_disconnect(xendev, &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
+ xen_block_disconnect(xendev, errp);
+ if (*errp) {
break;
}
@@ -665,9 +661,9 @@ static void xen_block_blockdev_del(const char *node_name, Error **errp)
static char *xen_block_blockdev_add(const char *id, QDict *qdict,
Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
const char *driver = qdict_get_try_str(qdict, "driver");
BlockdevOptions *options = NULL;
- Error *local_err = NULL;
char *node_name;
Visitor *v;
@@ -688,10 +684,9 @@ static char *xen_block_blockdev_add(const char *id, QDict *qdict,
goto fail;
}
- qmp_blockdev_add(options, &local_err);
+ qmp_blockdev_add(options, errp);
- if (local_err) {
- error_propagate(errp, local_err);
+ if (*errp) {
goto fail;
}
@@ -710,14 +705,12 @@ fail:
static void xen_block_drive_destroy(XenBlockDrive *drive, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
char *node_name = drive->node_name;
if (node_name) {
- Error *local_err = NULL;
-
- xen_block_blockdev_del(node_name, &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
+ xen_block_blockdev_del(node_name, errp);
+ if (*errp) {
return;
}
g_free(node_name);
@@ -731,6 +724,7 @@ static XenBlockDrive *xen_block_drive_create(const char *id,
const char *device_type,
QDict *opts, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
const char *params = qdict_get_try_str(opts, "params");
const char *mode = qdict_get_try_str(opts, "mode");
const char *direct_io_safe = qdict_get_try_str(opts, "direct-io-safe");
@@ -738,7 +732,6 @@ static XenBlockDrive *xen_block_drive_create(const char *id,
char *driver = NULL;
char *filename = NULL;
XenBlockDrive *drive = NULL;
- Error *local_err = NULL;
QDict *file_layer;
QDict *driver_layer;
@@ -817,13 +810,12 @@ static XenBlockDrive *xen_block_drive_create(const char *id,
g_assert(!drive->node_name);
drive->node_name = xen_block_blockdev_add(drive->id, driver_layer,
- &local_err);
+ errp);
qobject_unref(driver_layer);
done:
- if (local_err) {
- error_propagate(errp, local_err);
+ if (*errp) {
xen_block_drive_destroy(drive, NULL);
return NULL;
}
@@ -848,8 +840,8 @@ static void xen_block_iothread_destroy(XenBlockIOThread *iothread,
static XenBlockIOThread *xen_block_iothread_create(const char *id,
Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
XenBlockIOThread *iothread = g_new(XenBlockIOThread, 1);
- Error *local_err = NULL;
QDict *opts;
QObject *ret_data = NULL;
@@ -858,13 +850,11 @@ static XenBlockIOThread *xen_block_iothread_create(const char *id,
opts = qdict_new();
qdict_put_str(opts, "qom-type", TYPE_IOTHREAD);
qdict_put_str(opts, "id", id);
- qmp_object_add(opts, &ret_data, &local_err);
+ qmp_object_add(opts, &ret_data, errp);
qobject_unref(opts);
qobject_unref(ret_data);
- if (local_err) {
- error_propagate(errp, local_err);
-
+ if (*errp) {
g_free(iothread->id);
g_free(iothread);
return NULL;
@@ -876,6 +866,7 @@ static XenBlockIOThread *xen_block_iothread_create(const char *id,
static void xen_block_device_create(XenBackendInstance *backend,
QDict *opts, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
XenBus *xenbus = xen_backend_get_bus(backend);
const char *name = xen_backend_get_name(backend);
unsigned long number;
@@ -883,7 +874,6 @@ static void xen_block_device_create(XenBackendInstance *backend,
XenBlockDrive *drive = NULL;
XenBlockIOThread *iothread = NULL;
XenDevice *xendev = NULL;
- Error *local_err = NULL;
const char *type;
XenBlockDevice *blockdev;
@@ -915,16 +905,15 @@ static void xen_block_device_create(XenBackendInstance *backend,
goto fail;
}
- drive = xen_block_drive_create(vdev, device_type, opts, &local_err);
+ drive = xen_block_drive_create(vdev, device_type, opts, errp);
if (!drive) {
- error_propagate_prepend(errp, local_err, "failed to create drive: ");
+ error_prepend(errp, "failed to create drive: ");
goto fail;
}
- iothread = xen_block_iothread_create(vdev, &local_err);
- if (local_err) {
- error_propagate_prepend(errp, local_err,
- "failed to create iothread: ");
+ iothread = xen_block_iothread_create(vdev, errp);
+ if (*errp) {
+ error_prepend(errp, "failed to create iothread: ");
goto fail;
}
@@ -932,32 +921,29 @@ static void xen_block_device_create(XenBackendInstance *backend,
blockdev = XEN_BLOCK_DEVICE(xendev);
if (!object_property_set_str(OBJECT(xendev), "vdev", vdev,
- &local_err)) {
- error_propagate_prepend(errp, local_err, "failed to set 'vdev': ");
+ errp)) {
+ error_prepend(errp, "failed to set 'vdev': ");
goto fail;
}
if (!object_property_set_str(OBJECT(xendev), "drive",
xen_block_drive_get_node_name(drive),
- &local_err)) {
- error_propagate_prepend(errp, local_err, "failed to set 'drive': ");
+ errp)) {
+ error_prepend(errp, "failed to set 'drive': ");
goto fail;
}
if (!object_property_set_str(OBJECT(xendev), "iothread", iothread->id,
- &local_err)) {
- error_propagate_prepend(errp, local_err,
- "failed to set 'iothread': ");
+ errp)) {
+ error_prepend(errp, "failed to set 'iothread': ");
goto fail;
}
blockdev->iothread = iothread;
blockdev->drive = drive;
- if (!qdev_realize_and_unref(DEVICE(xendev), BUS(xenbus), &local_err)) {
- error_propagate_prepend(errp, local_err,
- "realization of device %s failed: ",
- type);
+ if (!qdev_realize_and_unref(DEVICE(xendev), BUS(xenbus), errp)) {
+ error_prepend(errp, "realization of device %s failed: ", type);
goto fail;
}
@@ -981,31 +967,29 @@ fail:
static void xen_block_device_destroy(XenBackendInstance *backend,
Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
XenDevice *xendev = xen_backend_get_device(backend);
XenBlockDevice *blockdev = XEN_BLOCK_DEVICE(xendev);
XenBlockVdev *vdev = &blockdev->props.vdev;
XenBlockDrive *drive = blockdev->drive;
XenBlockIOThread *iothread = blockdev->iothread;
- Error *local_err = NULL;
trace_xen_block_device_destroy(vdev->number);
object_unparent(OBJECT(xendev));
if (iothread) {
- xen_block_iothread_destroy(iothread, &local_err);
- if (local_err) {
- error_propagate_prepend(errp, local_err,
- "failed to destroy iothread: ");
+ xen_block_iothread_destroy(iothread, errp);
+ if (*errp) {
+ error_prepend(errp, "failed to destroy iothread: ");
return;
}
}
if (drive) {
- xen_block_drive_destroy(drive, &local_err);
- if (local_err) {
- error_propagate_prepend(errp, local_err,
- "failed to destroy drive: ");
+ xen_block_drive_destroy(drive, errp);
+ if (*errp) {
+ error_prepend(errp, "failed to destroy drive: ");
return;
}
}
diff --git a/hw/pci-host/xen_igd_pt.c b/hw/pci-host/xen_igd_pt.c
index efcc9347ff..29ade9ca25 100644
--- a/hw/pci-host/xen_igd_pt.c
+++ b/hw/pci-host/xen_igd_pt.c
@@ -79,17 +79,16 @@ static void host_pci_config_read(int pos, int len, uint32_t *val, Error **errp)
static void igd_pt_i440fx_realize(PCIDevice *pci_dev, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
uint32_t val = 0;
size_t i;
int pos, len;
- Error *local_err = NULL;
for (i = 0; i < ARRAY_SIZE(igd_host_bridge_infos); i++) {
pos = igd_host_bridge_infos[i].offset;
len = igd_host_bridge_infos[i].len;
- host_pci_config_read(pos, len, &val, &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
+ host_pci_config_read(pos, len, &val, errp);
+ if (*errp) {
return;
}
pci_default_write_config(pci_dev, pos, val, len);
diff --git a/hw/xen/xen-backend.c b/hw/xen/xen-backend.c
index da065f81b7..1cc0694053 100644
--- a/hw/xen/xen-backend.c
+++ b/hw/xen/xen-backend.c
@@ -98,9 +98,9 @@ static void xen_backend_list_remove(XenBackendInstance *backend)
void xen_backend_device_create(XenBus *xenbus, const char *type,
const char *name, QDict *opts, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
const XenBackendImpl *impl = xen_backend_table_lookup(type);
XenBackendInstance *backend;
- Error *local_error = NULL;
if (!impl) {
return;
@@ -110,9 +110,8 @@ void xen_backend_device_create(XenBus *xenbus, const char *type,
backend->xenbus = xenbus;
backend->name = g_strdup(name);
- impl->create(backend, opts, &local_error);
- if (local_error) {
- error_propagate(errp, local_error);
+ impl->create(backend, opts, errp);
+ if (*errp) {
g_free(backend->name);
g_free(backend);
return;
diff --git a/hw/xen/xen-bus.c b/hw/xen/xen-bus.c
index c4e2162ae9..2ea5144ef0 100644
--- a/hw/xen/xen-bus.c
+++ b/hw/xen/xen-bus.c
@@ -53,9 +53,9 @@ static char *xen_device_get_frontend_path(XenDevice *xendev)
static void xen_device_unplug(XenDevice *xendev, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
XenBus *xenbus = XEN_BUS(qdev_get_parent_bus(DEVICE(xendev)));
const char *type = object_get_typename(OBJECT(xendev));
- Error *local_err = NULL;
xs_transaction_t tid;
trace_xen_device_unplug(type, xendev->name);
@@ -69,14 +69,14 @@ again:
}
xs_node_printf(xenbus->xsh, tid, xendev->backend_path, "online",
- &local_err, "%u", 0);
- if (local_err) {
+ errp, "%u", 0);
+ if (*errp) {
goto abort;
}
xs_node_printf(xenbus->xsh, tid, xendev->backend_path, "state",
- &local_err, "%u", XenbusStateClosing);
- if (local_err) {
+ errp, "%u", XenbusStateClosing);
+ if (*errp) {
goto abort;
}
@@ -96,7 +96,6 @@ abort:
* from ending the transaction.
*/
xs_transaction_end(xenbus->xsh, tid, true);
- error_propagate(errp, local_err);
}
static void xen_bus_print_dev(Monitor *mon, DeviceState *dev, int indent)
@@ -205,15 +204,13 @@ static XenWatch *watch_list_add(XenWatchList *watch_list, const char *node,
const char *key, XenWatchHandler handler,
void *opaque, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
XenWatch *watch = new_watch(node, key, handler, opaque);
- Error *local_err = NULL;
notifier_list_add(&watch_list->notifiers, &watch->notifier);
- xs_node_watch(watch_list->xsh, node, key, watch->token, &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
-
+ xs_node_watch(watch_list->xsh, node, key, watch->token, errp);
+ if (*errp) {
notifier_remove(&watch->notifier);
free_watch(watch);
@@ -255,11 +252,11 @@ static void xen_bus_backend_create(XenBus *xenbus, const char *type,
const char *name, char *path,
Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
xs_transaction_t tid;
char **key;
QDict *opts;
unsigned int i, n;
- Error *local_err = NULL;
trace_xen_bus_backend_create(type, path);
@@ -314,13 +311,11 @@ again:
return;
}
- xen_backend_device_create(xenbus, type, name, opts, &local_err);
+ xen_backend_device_create(xenbus, type, name, opts, errp);
qobject_unref(opts);
- if (local_err) {
- error_propagate_prepend(errp, local_err,
- "failed to create '%s' device '%s': ",
- type, name);
+ if (*errp) {
+ error_prepend(errp, "failed to create '%s' device '%s': ", type, name);
}
}
@@ -692,9 +687,9 @@ static void xen_device_remove_watch(XenDevice *xendev, XenWatch *watch,
static void xen_device_backend_create(XenDevice *xendev, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
XenBus *xenbus = XEN_BUS(qdev_get_parent_bus(DEVICE(xendev)));
struct xs_permissions perms[2];
- Error *local_err = NULL;
xendev->backend_path = xen_device_get_backend_path(xendev);
@@ -706,30 +701,27 @@ static void xen_device_backend_create(XenDevice *xendev, Error **errp)
g_assert(xenbus->xsh);
xs_node_create(xenbus->xsh, XBT_NULL, xendev->backend_path, perms,
- ARRAY_SIZE(perms), &local_err);
- if (local_err) {
- error_propagate_prepend(errp, local_err,
- "failed to create backend: ");
+ ARRAY_SIZE(perms), errp);
+ if (*errp) {
+ error_prepend(errp, "failed to create backend: ");
return;
}
xendev->backend_state_watch =
xen_device_add_watch(xendev, xendev->backend_path,
"state", xen_device_backend_changed,
- &local_err);
- if (local_err) {
- error_propagate_prepend(errp, local_err,
- "failed to watch backend state: ");
+ errp);
+ if (*errp) {
+ error_prepend(errp, "failed to watch backend state: ");
return;
}
xendev->backend_online_watch =
xen_device_add_watch(xendev, xendev->backend_path,
"online", xen_device_backend_changed,
- &local_err);
- if (local_err) {
- error_propagate_prepend(errp, local_err,
- "failed to watch backend online: ");
+ errp);
+ if (*errp) {
+ error_prepend(errp, "failed to watch backend online: ");
return;
}
}
@@ -866,9 +858,9 @@ static bool xen_device_frontend_exists(XenDevice *xendev)
static void xen_device_frontend_create(XenDevice *xendev, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
XenBus *xenbus = XEN_BUS(qdev_get_parent_bus(DEVICE(xendev)));
struct xs_permissions perms[2];
- Error *local_err = NULL;
xendev->frontend_path = xen_device_get_frontend_path(xendev);
@@ -885,20 +877,18 @@ static void xen_device_frontend_create(XenDevice *xendev, Error **errp)
g_assert(xenbus->xsh);
xs_node_create(xenbus->xsh, XBT_NULL, xendev->frontend_path, perms,
- ARRAY_SIZE(perms), &local_err);
- if (local_err) {
- error_propagate_prepend(errp, local_err,
- "failed to create frontend: ");
+ ARRAY_SIZE(perms), errp);
+ if (*errp) {
+ error_prepend(errp, "failed to create frontend: ");
return;
}
}
xendev->frontend_state_watch =
xen_device_add_watch(xendev, xendev->frontend_path, "state",
- xen_device_frontend_changed, &local_err);
- if (local_err) {
- error_propagate_prepend(errp, local_err,
- "failed to watch frontend state: ");
+ xen_device_frontend_changed, errp);
+ if (*errp) {
+ error_prepend(errp, "failed to watch frontend state: ");
}
}
@@ -1247,11 +1237,11 @@ static void xen_device_exit(Notifier *n, void *data)
static void xen_device_realize(DeviceState *dev, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
XenDevice *xendev = XEN_DEVICE(dev);
XenDeviceClass *xendev_class = XEN_DEVICE_GET_CLASS(xendev);
XenBus *xenbus = XEN_BUS(qdev_get_parent_bus(DEVICE(xendev)));
const char *type = object_get_typename(OBJECT(xendev));
- Error *local_err = NULL;
if (xendev->frontend_id == DOMID_INVALID) {
xendev->frontend_id = xen_domid;
@@ -1267,10 +1257,9 @@ static void xen_device_realize(DeviceState *dev, Error **errp)
goto unrealize;
}
- xendev->name = xendev_class->get_name(xendev, &local_err);
- if (local_err) {
- error_propagate_prepend(errp, local_err,
- "failed to get device name: ");
+ xendev->name = xendev_class->get_name(xendev, errp);
+ if (*errp) {
+ error_prepend(errp, "failed to get device name: ");
goto unrealize;
}
@@ -1293,22 +1282,19 @@ static void xen_device_realize(DeviceState *dev, Error **errp)
xendev->feature_grant_copy =
(xengnttab_grant_copy(xendev->xgth, 0, NULL) == 0);
- xen_device_backend_create(xendev, &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
+ xen_device_backend_create(xendev, errp);
+ if (*errp) {
goto unrealize;
}
- xen_device_frontend_create(xendev, &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
+ xen_device_frontend_create(xendev, errp);
+ if (*errp) {
goto unrealize;
}
if (xendev_class->realize) {
- xendev_class->realize(xendev, &local_err);
- if (local_err) {
- error_propagate(errp, local_err);
+ xendev_class->realize(xendev, errp);
+ if (*errp) {
goto unrealize;
}
}
diff --git a/hw/xen/xen-host-pci-device.c b/hw/xen/xen-host-pci-device.c
index 1b44dcafaf..02379c341c 100644
--- a/hw/xen/xen-host-pci-device.c
+++ b/hw/xen/xen-host-pci-device.c
@@ -333,8 +333,8 @@ void xen_host_pci_device_get(XenHostPCIDevice *d, uint16_t domain,
uint8_t bus, uint8_t dev, uint8_t func,
Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
unsigned int v;
- Error *err = NULL;
d->config_fd = -1;
d->domain = domain;
@@ -342,36 +342,36 @@ void xen_host_pci_device_get(XenHostPCIDevice *d, uint16_t domain,
d->dev = dev;
d->func = func;
- xen_host_pci_config_open(d, &err);
- if (err) {
+ xen_host_pci_config_open(d, errp);
+ if (*errp) {
goto error;
}
- xen_host_pci_get_resource(d, &err);
- if (err) {
+ xen_host_pci_get_resource(d, errp);
+ if (*errp) {
goto error;
}
- xen_host_pci_get_hex_value(d, "vendor", &v, &err);
- if (err) {
+ xen_host_pci_get_hex_value(d, "vendor", &v, errp);
+ if (*errp) {
goto error;
}
d->vendor_id = v;
- xen_host_pci_get_hex_value(d, "device", &v, &err);
- if (err) {
+ xen_host_pci_get_hex_value(d, "device", &v, errp);
+ if (*errp) {
goto error;
}
d->device_id = v;
- xen_host_pci_get_dec_value(d, "irq", &v, &err);
- if (err) {
+ xen_host_pci_get_dec_value(d, "irq", &v, errp);
+ if (*errp) {
goto error;
}
d->irq = v;
- xen_host_pci_get_hex_value(d, "class", &v, &err);
- if (err) {
+ xen_host_pci_get_hex_value(d, "class", &v, errp);
+ if (*errp) {
goto error;
}
d->class_code = v;
@@ -381,7 +381,6 @@ void xen_host_pci_device_get(XenHostPCIDevice *d, uint16_t domain,
return;
error:
- error_propagate(errp, err);
if (d->config_fd >= 0) {
close(d->config_fd);
diff --git a/hw/xen/xen_pt.c b/hw/xen/xen_pt.c
index ab84443d5e..baa25eb91a 100644
--- a/hw/xen/xen_pt.c
+++ b/hw/xen/xen_pt.c
@@ -777,12 +777,12 @@ static void xen_pt_destroy(PCIDevice *d) {
static void xen_pt_realize(PCIDevice *d, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
XenPCIPassthroughState *s = XEN_PT_DEVICE(d);
int i, rc = 0;
uint8_t machine_irq = 0, scratch;
uint16_t cmd = 0;
int pirq = XEN_PT_UNASSIGNED_PIRQ;
- Error *err = NULL;
/* register real device */
XEN_PT_LOG(d, "Assigning real physical device %02x:%02x.%d"
@@ -793,10 +793,9 @@ static void xen_pt_realize(PCIDevice *d, Error **errp)
xen_host_pci_device_get(&s->real_device,
s->hostaddr.domain, s->hostaddr.bus,
s->hostaddr.slot, s->hostaddr.function,
- &err);
- if (err) {
- error_append_hint(&err, "Failed to \"open\" the real pci device");
- error_propagate(errp, err);
+ errp);
+ if (*errp) {
+ error_append_hint(errp, "Failed to \"open\" the real pci device");
return;
}
@@ -823,11 +822,10 @@ static void xen_pt_realize(PCIDevice *d, Error **errp)
return;
}
- xen_pt_setup_vga(s, &s->real_device, &err);
- if (err) {
- error_append_hint(&err, "Setup VGA BIOS of passthrough"
- " GFX failed");
- error_propagate(errp, err);
+ xen_pt_setup_vga(s, &s->real_device, errp);
+ if (*errp) {
+ error_append_hint(errp, "Setup VGA BIOS of passthrough"
+ " GFX failed");
xen_host_pci_device_put(&s->real_device);
return;
}
@@ -840,10 +838,9 @@ static void xen_pt_realize(PCIDevice *d, Error **errp)
xen_pt_register_regions(s, &cmd);
/* reinitialize each config register to be emulated */
- xen_pt_config_init(s, &err);
- if (err) {
- error_append_hint(&err, "PCI Config space initialisation failed");
- error_propagate(errp, err);
+ xen_pt_config_init(s, errp);
+ if (*errp) {
+ error_append_hint(errp, "PCI Config space initialisation failed");
rc = -1;
goto err_out;
}
diff --git a/hw/xen/xen_pt_config_init.c b/hw/xen/xen_pt_config_init.c
index d0d7c720a6..af3fbd1bfb 100644
--- a/hw/xen/xen_pt_config_init.c
+++ b/hw/xen/xen_pt_config_init.c
@@ -2008,8 +2008,8 @@ static void xen_pt_config_reg_init(XenPCIPassthroughState *s,
void xen_pt_config_init(XenPCIPassthroughState *s, Error **errp)
{
+ ERRP_AUTO_PROPAGATE();
int i, rc;
- Error *err = NULL;
QLIST_INIT(&s->reg_grps);
@@ -2067,13 +2067,14 @@ void xen_pt_config_init(XenPCIPassthroughState *s, Error **errp)
/* initialize capability register */
for (j = 0; regs->size != 0; j++, regs++) {
- xen_pt_config_reg_init(s, reg_grp_entry, regs, &err);
- if (err) {
- error_append_hint(&err, "Failed to init register %d"
- " offsets 0x%x in grp_type = 0x%x (%d/%zu)", j,
- regs->offset, xen_pt_emu_reg_grps[i].grp_type,
- i, ARRAY_SIZE(xen_pt_emu_reg_grps));
- error_propagate(errp, err);
+ xen_pt_config_reg_init(s, reg_grp_entry, regs, errp);
+ if (*errp) {
+ error_append_hint(errp, "Failed to init register %d"
+ " offsets 0x%x in grp_type = 0x%x (%d/%zu)",
+ j,
+ regs->offset,
+ xen_pt_emu_reg_grps[i].grp_type,
+ i, ARRAY_SIZE(xen_pt_emu_reg_grps));
xen_pt_config_delete(s);
return;
}
--
2.21.0
^ permalink raw reply related [flat|nested] 16+ messages in thread
* Re: [PATCH v11 3/8] SD (Secure Card): introduce ERRP_AUTO_PROPAGATE
2020-07-03 9:08 ` [PATCH v11 3/8] SD (Secure Card): introduce ERRP_AUTO_PROPAGATE Vladimir Sementsov-Ogievskiy
@ 2020-07-04 16:28 ` Philippe Mathieu-Daudé
0 siblings, 0 replies; 16+ messages in thread
From: Philippe Mathieu-Daudé @ 2020-07-04 16:28 UTC (permalink / raw)
To: Vladimir Sementsov-Ogievskiy, qemu-devel; +Cc: Kevin Wolf, armbru, groug
On 7/3/20 11:08 AM, Vladimir Sementsov-Ogievskiy wrote:
> If we want to add some info to errp (by error_prepend() or
> error_append_hint()), we must use the ERRP_AUTO_PROPAGATE macro.
> Otherwise, this info will not be added when errp == &error_fatal
> (the program will exit prior to the error_append_hint() or
> error_prepend() call). Fix such cases.
>
> If we want to check error after errp-function call, we need to
> introduce local_err and then propagate it to errp. Instead, use
> ERRP_AUTO_PROPAGATE macro, benefits are:
> 1. No need of explicit error_propagate call
> 2. No need of explicit local_err variable: use errp directly
> 3. ERRP_AUTO_PROPAGATE leaves errp as is if it's not NULL or
> &error_fatal, this means that we don't break error_abort
> (we'll abort on error_set, not on error_propagate)
>
> This commit is generated by command
>
> sed -n '/^SD (Secure Card)$/,/^$/{s/^F: //p}' \
> MAINTAINERS | \
> xargs git ls-files | grep '\.[hc]$' | \
> xargs spatch \
> --sp-file scripts/coccinelle/auto-propagated-errp.cocci \
> --macro-file scripts/cocci-macro-file.h \
> --in-place --no-show-diff --max-width 80
>
> Reported-by: Kevin Wolf <kwolf@redhat.com>
> Reported-by: Greg Kurz <groug@kaod.org>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
If possible 's/SD (Secure Card)/sd/' in subject.
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> ---
> hw/sd/sdhci-pci.c | 7 +++----
> hw/sd/sdhci.c | 21 +++++++++------------
> hw/sd/ssi-sd.c | 10 +++++-----
> 3 files changed, 17 insertions(+), 21 deletions(-)
>
> diff --git a/hw/sd/sdhci-pci.c b/hw/sd/sdhci-pci.c
> index 4f5977d487..38ec572fc6 100644
> --- a/hw/sd/sdhci-pci.c
> +++ b/hw/sd/sdhci-pci.c
> @@ -29,13 +29,12 @@ static Property sdhci_pci_properties[] = {
>
> static void sdhci_pci_realize(PCIDevice *dev, Error **errp)
> {
> + ERRP_AUTO_PROPAGATE();
> SDHCIState *s = PCI_SDHCI(dev);
> - Error *local_err = NULL;
>
> sdhci_initfn(s);
> - sdhci_common_realize(s, &local_err);
> - if (local_err) {
> - error_propagate(errp, local_err);
> + sdhci_common_realize(s, errp);
> + if (*errp) {
> return;
> }
>
> diff --git a/hw/sd/sdhci.c b/hw/sd/sdhci.c
> index eb2be6529e..be1928784d 100644
> --- a/hw/sd/sdhci.c
> +++ b/hw/sd/sdhci.c
> @@ -1288,7 +1288,7 @@ static const MemoryRegionOps sdhci_mmio_ops = {
>
> static void sdhci_init_readonly_registers(SDHCIState *s, Error **errp)
> {
> - Error *local_err = NULL;
> + ERRP_AUTO_PROPAGATE();
>
> switch (s->sd_spec_version) {
> case 2 ... 3:
> @@ -1299,9 +1299,8 @@ static void sdhci_init_readonly_registers(SDHCIState *s, Error **errp)
> }
> s->version = (SDHC_HCVER_VENDOR << 8) | (s->sd_spec_version - 1);
>
> - sdhci_check_capareg(s, &local_err);
> - if (local_err) {
> - error_propagate(errp, local_err);
> + sdhci_check_capareg(s, errp);
> + if (*errp) {
> return;
> }
> }
> @@ -1332,11 +1331,10 @@ void sdhci_uninitfn(SDHCIState *s)
>
> void sdhci_common_realize(SDHCIState *s, Error **errp)
> {
> - Error *local_err = NULL;
> + ERRP_AUTO_PROPAGATE();
>
> - sdhci_init_readonly_registers(s, &local_err);
> - if (local_err) {
> - error_propagate(errp, local_err);
> + sdhci_init_readonly_registers(s, errp);
> + if (*errp) {
> return;
> }
> s->buf_maxsz = sdhci_get_fifolen(s);
> @@ -1456,13 +1454,12 @@ static void sdhci_sysbus_finalize(Object *obj)
>
> static void sdhci_sysbus_realize(DeviceState *dev, Error **errp)
> {
> + ERRP_AUTO_PROPAGATE();
> SDHCIState *s = SYSBUS_SDHCI(dev);
> SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
> - Error *local_err = NULL;
>
> - sdhci_common_realize(s, &local_err);
> - if (local_err) {
> - error_propagate(errp, local_err);
> + sdhci_common_realize(s, errp);
> + if (*errp) {
> return;
> }
>
> diff --git a/hw/sd/ssi-sd.c b/hw/sd/ssi-sd.c
> index e0fb9f3093..43e5730b00 100644
> --- a/hw/sd/ssi-sd.c
> +++ b/hw/sd/ssi-sd.c
> @@ -241,10 +241,10 @@ static const VMStateDescription vmstate_ssi_sd = {
>
> static void ssi_sd_realize(SSISlave *d, Error **errp)
> {
> + ERRP_AUTO_PROPAGATE();
> ssi_sd_state *s = FROM_SSI_SLAVE(ssi_sd_state, d);
> DeviceState *carddev;
> DriveInfo *dinfo;
> - Error *err = NULL;
>
> qbus_create_inplace(&s->sdbus, sizeof(s->sdbus), TYPE_SD_BUS,
> DEVICE(d), "sd-bus");
> @@ -255,23 +255,23 @@ static void ssi_sd_realize(SSISlave *d, Error **errp)
> carddev = qdev_new(TYPE_SD_CARD);
> if (dinfo) {
> if (!qdev_prop_set_drive_err(carddev, "drive",
> - blk_by_legacy_dinfo(dinfo), &err)) {
> + blk_by_legacy_dinfo(dinfo), errp)) {
> goto fail;
> }
> }
>
> - if (!object_property_set_bool(OBJECT(carddev), "spi", true, &err)) {
> + if (!object_property_set_bool(OBJECT(carddev), "spi", true, errp)) {
> goto fail;
> }
>
> - if (!qdev_realize_and_unref(carddev, BUS(&s->sdbus), &err)) {
> + if (!qdev_realize_and_unref(carddev, BUS(&s->sdbus), errp)) {
> goto fail;
> }
>
> return;
>
> fail:
> - error_propagate_prepend(errp, err, "failed to init SD card: ");
> + error_prepend(errp, "failed to init SD card: ");
> }
>
> static void ssi_sd_reset(DeviceState *dev)
>
^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH v11 8/8] xen: introduce ERRP_AUTO_PROPAGATE
2020-07-03 9:08 ` [PATCH v11 8/8] xen: " Vladimir Sementsov-Ogievskiy
@ 2020-07-04 16:36 ` Philippe Mathieu-Daudé
2020-07-06 7:41 ` Markus Armbruster
2020-07-06 7:55 ` Vladimir Sementsov-Ogievskiy
0 siblings, 2 replies; 16+ messages in thread
From: Philippe Mathieu-Daudé @ 2020-07-04 16:36 UTC (permalink / raw)
To: Vladimir Sementsov-Ogievskiy, qemu-devel
Cc: Kevin Wolf, Stefano Stabellini, qemu-block, Paul Durrant, groug,
armbru, Stefan Hajnoczi, Anthony Perard, xen-devel, Max Reitz
On 7/3/20 11:08 AM, Vladimir Sementsov-Ogievskiy wrote:
> If we want to add some info to errp (by error_prepend() or
> error_append_hint()), we must use the ERRP_AUTO_PROPAGATE macro.
> Otherwise, this info will not be added when errp == &error_fatal
> (the program will exit prior to the error_append_hint() or
> error_prepend() call). Fix such cases.
>
> If we want to check error after errp-function call, we need to
> introduce local_err and then propagate it to errp. Instead, use
> ERRP_AUTO_PROPAGATE macro, benefits are:
> 1. No need of explicit error_propagate call
> 2. No need of explicit local_err variable: use errp directly
> 3. ERRP_AUTO_PROPAGATE leaves errp as is if it's not NULL or
> &error_fatal, this means that we don't break error_abort
> (we'll abort on error_set, not on error_propagate)
>
> This commit is generated by command
>
> sed -n '/^X86 Xen CPUs$/,/^$/{s/^F: //p}' MAINTAINERS | \
> xargs git ls-files | grep '\.[hc]$' | \
> xargs spatch \
> --sp-file scripts/coccinelle/auto-propagated-errp.cocci \
> --macro-file scripts/cocci-macro-file.h \
> --in-place --no-show-diff --max-width 80
>
> Reported-by: Kevin Wolf <kwolf@redhat.com>
> Reported-by: Greg Kurz <groug@kaod.org>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
> hw/block/dataplane/xen-block.c | 17 +++---
> hw/block/xen-block.c | 102 ++++++++++++++-------------------
> hw/pci-host/xen_igd_pt.c | 7 +--
> hw/xen/xen-backend.c | 7 +--
> hw/xen/xen-bus.c | 92 +++++++++++++----------------
> hw/xen/xen-host-pci-device.c | 27 +++++----
> hw/xen/xen_pt.c | 25 ++++----
> hw/xen/xen_pt_config_init.c | 17 +++---
> 8 files changed, 128 insertions(+), 166 deletions(-)
Without the description, this patch has 800 lines of diff...
It killed me, I don't have the energy to review patch #7 of this
series after that, sorry.
Consider splitting such mechanical patches next time. Here it
could have been hw/block, hw/pci-host, hw/xen.
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH v11 7/8] nbd: introduce ERRP_AUTO_PROPAGATE
2020-07-03 9:08 ` [PATCH v11 7/8] nbd: " Vladimir Sementsov-Ogievskiy
@ 2020-07-06 5:22 ` Markus Armbruster
2020-07-07 11:51 ` Markus Armbruster
1 sibling, 0 replies; 16+ messages in thread
From: Markus Armbruster @ 2020-07-06 5:22 UTC (permalink / raw)
To: Vladimir Sementsov-Ogievskiy
Cc: Kevin Wolf, groug, qemu-devel, qemu-block, Max Reitz
Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> writes:
> If we want to add some info to errp (by error_prepend() or
> error_append_hint()), we must use the ERRP_AUTO_PROPAGATE macro.
> Otherwise, this info will not be added when errp == &error_fatal
> (the program will exit prior to the error_append_hint() or
> error_prepend() call). Fix such cases.
>
> If we want to check error after errp-function call, we need to
> introduce local_err and then propagate it to errp. Instead, use
> ERRP_AUTO_PROPAGATE macro, benefits are:
> 1. No need of explicit error_propagate call
> 2. No need of explicit local_err variable: use errp directly
> 3. ERRP_AUTO_PROPAGATE leaves errp as is if it's not NULL or
> &error_fatal, this means that we don't break error_abort
> (we'll abort on error_set, not on error_propagate)
>
> This commit is generated by command
>
> sed -n '/^Network Block Device (NBD)$/,/^$/{s/^F: //p}' \
> MAINTAINERS | \
> xargs git ls-files | grep '\.[hc]$' | \
> xargs spatch \
> --sp-file scripts/coccinelle/auto-propagated-errp.cocci \
> --macro-file scripts/cocci-macro-file.h \
> --in-place --no-show-diff --max-width 80
>
> Reported-by: Kevin Wolf <kwolf@redhat.com>
> Reported-by: Greg Kurz <groug@kaod.org>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH v11 1/8] error: auto propagated local_err
2020-07-03 9:08 ` [PATCH v11 1/8] error: auto propagated local_err Vladimir Sementsov-Ogievskiy
@ 2020-07-06 5:59 ` Markus Armbruster
0 siblings, 0 replies; 16+ messages in thread
From: Markus Armbruster @ 2020-07-06 5:59 UTC (permalink / raw)
To: Vladimir Sementsov-Ogievskiy
Cc: Kevin Wolf, Stefano Stabellini, Michael Roth, qemu-block,
Paul Durrant, Laszlo Ersek, Christian Schoenebeck, qemu-devel,
groug, Gerd Hoffmann, Stefan Hajnoczi, Anthony Perard, xen-devel,
Max Reitz, Philippe Mathieu-Daudé
Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> writes:
> Introduce a new ERRP_AUTO_PROPAGATE macro, to be used at start of
> functions with an errp OUT parameter.
>
> It has three goals:
>
> 1. Fix issue with error_fatal and error_prepend/error_append_hint: user
> can't see this additional information, because exit() happens in
> error_setg earlier than information is added. [Reported by Greg Kurz]
>
> 2. Fix issue with error_abort and error_propagate: when we wrap
> error_abort by local_err+error_propagate, the resulting coredump will
> refer to error_propagate and not to the place where error happened.
> (the macro itself doesn't fix the issue, but it allows us to [3.] drop
> the local_err+error_propagate pattern, which will definitely fix the
> issue) [Reported by Kevin Wolf]
>
> 3. Drop local_err+error_propagate pattern, which is used to workaround
> void functions with errp parameter, when caller wants to know resulting
> status. (Note: actually these functions could be merely updated to
> return int error code).
>
> To achieve these goals, later patches will add invocations
> of this macro at the start of functions with either use
> error_prepend/error_append_hint (solving 1) or which use
> local_err+error_propagate to check errors, switching those
> functions to use *errp instead (solving 2 and 3).
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> Reviewed-by: Paul Durrant <paul@xen.org>
> Reviewed-by: Greg Kurz <groug@kaod.org>
> Reviewed-by: Eric Blake <eblake@redhat.com>
> ---
>
> Cc: Eric Blake <eblake@redhat.com>
> Cc: Kevin Wolf <kwolf@redhat.com>
> Cc: Max Reitz <mreitz@redhat.com>
> Cc: Greg Kurz <groug@kaod.org>
> Cc: Christian Schoenebeck <qemu_oss@crudebyte.com>
> Cc: Stefan Hajnoczi <stefanha@redhat.com>
> Cc: Stefano Stabellini <sstabellini@kernel.org>
> Cc: Anthony Perard <anthony.perard@citrix.com>
> Cc: Paul Durrant <paul@xen.org>
> Cc: "Philippe Mathieu-Daudé" <philmd@redhat.com>
> Cc: Laszlo Ersek <lersek@redhat.com>
> Cc: Gerd Hoffmann <kraxel@redhat.com>
> Cc: Markus Armbruster <armbru@redhat.com>
> Cc: Michael Roth <mdroth@linux.vnet.ibm.com>
> Cc: qemu-devel@nongnu.org
> Cc: qemu-block@nongnu.org
> Cc: xen-devel@lists.xenproject.org
>
> include/qapi/error.h | 205 ++++++++++++++++++++++++++++++++++++-------
> 1 file changed, 172 insertions(+), 33 deletions(-)
>
> diff --git a/include/qapi/error.h b/include/qapi/error.h
> index 5ceb3ace06..b54aedbfd7 100644
> --- a/include/qapi/error.h
> +++ b/include/qapi/error.h
> @@ -39,7 +39,7 @@
> * • pointer-valued functions return non-null / null pointer, and
> * • integer-valued functions return non-negative / negative.
> *
> - * How to:
> + * = Deal with Error object =
> *
> * Create an error:
> * error_setg(errp, "situation normal, all fouled up");
> @@ -73,28 +73,91 @@
> * reporting it (primarily useful in testsuites):
> * error_free_or_abort(&err);
> *
> - * Pass an existing error to the caller:
> - * error_propagate(errp, err);
> - * where Error **errp is a parameter, by convention the last one.
> + * = Deal with Error ** function parameter =
> *
> - * Pass an existing error to the caller with the message modified:
> - * error_propagate_prepend(errp, err);
> + * A function may use the error system to return errors. In this case, the
> + * function defines an Error **errp parameter, by convention the last one (with
> + * exceptions for functions using ... or va_list).
> *
> - * Avoid
> - * error_propagate(errp, err);
> - * error_prepend(errp, "Could not frobnicate '%s': ", name);
> - * because this fails to prepend when @errp is &error_fatal.
> + * The caller may then pass in the following errp values:
> + *
> + * 1. &error_abort
> + * Any error will result in abort().
> + * 2. &error_fatal
> + * Any error will result in exit() with a non-zero status.
> + * 3. NULL
> + * No error reporting through errp parameter.
> + * 4. The address of a NULL-initialized Error *err
> + * Any error will populate errp with an error object.
The rebase onto my "error: Document Error API usage rules" rendered this
this partly redundant. I'll try my hand at a proper merge, then ask you
to check it.
Should I fail to complete this in time for the soft freeze, we can merge
the thing as is. Comment improvements are fair game until -rc1 or so.
> *
> - * Create a new error and pass it to the caller:
> + * The following rules then implement the correct semantics desired by the
> + * caller.
> + *
> + * Create a new error to pass to the caller:
> * error_setg(errp, "situation normal, all fouled up");
> *
> - * Call a function and receive an error from it:
> + * Calling another errp-based function:
> + * f(..., errp);
> + *
> + * == Checking success of subcall ==
> + *
> + * If a function returns a value indicating an error in addition to setting
> + * errp (which is recommended), then you don't need any additional code, just
> + * do:
> + *
> + * int ret = f(..., errp);
> + * if (ret < 0) {
> + * ... handle error ...
> + * return ret;
> + * }
> + *
> + * If a function returns nothing (not recommended for new code), the only way
Also when a function returns something, but there is no distinct error
value. Example: object_property_get_int().
I shouldn't criticize comments without suggesting improvements. But
since I'm going to mess with this text anyway to merge your work with my
prior work, I take it easy and only note what I think needs work. I'll
then try to address all that in or on top of my merge.
> + * to check success is by consulting errp; doing this safely requires the use
> + * of the ERRP_AUTO_PROPAGATE macro, like this:
"Requires" is inaccurate. Using a local variable with error_propagate()
also works (there's even an example right below). We prefer
ERRP_AUTO_PROPAGATE(), because it's more readable and improves the
debugging experience.
> + *
> + * int our_func(..., Error **errp) {
A function's opening brace goes on its own line. More of the same below.
> + * ERRP_AUTO_PROPAGATE();
> + * ...
> + * subcall(..., errp);
> + * if (*errp) {
> + * ...
> + * return -EINVAL;
> + * }
> + * ...
> + * }
> + *
> + * ERRP_AUTO_PROPAGATE takes care of wrapping the original errp as needed, so
> + * that the rest of the function can directly use errp (including
> + * dereferencing), where any errors will then be propagated on to the original
> + * errp when leaving the function.
> + *
> + * In some cases, we need to check result of subcall, but do not want to
> + * propagate the Error object to our caller. In such cases we don't need
> + * ERRP_AUTO_PROPAGATE, but just a local Error object:
> + *
> + * Receive an error and not pass it:
> * Error *err = NULL;
> - * foo(arg, &err);
> + * subcall(arg, &err);
> * if (err) {
> * handle the error...
> + * error_free(err);
> * }
> *
> + * Note that older code that did not use ERRP_AUTO_PROPAGATE would instead need
> + * a local Error * variable and the use of error_propagate() to properly handle
> + * all possible caller values of errp. Now this is DEPRECATED* (see below).
I'd prefer not to shout DEPRECATED.
> + *
> + * Note that any function that wants to modify an error object, such as by
> + * calling error_append_hint or error_prepend, must use ERRP_AUTO_PROPAGATE, in
> + * order for a caller's use of &error_fatal to see the additional information.
"Must" should be reserved for situations where failure to adhere is
categorically wrong.
While we *want* people to use ERRP_AUTO_PROPAGATE() with
error_append_hint() and error_prepend(), failure to do so need not be
wrong.
Apropos error_append_hint(), the "Show errp instead of &err where &err
is actually unusual" part of my "error: Improve examples in error.h's
big comment" now feels premature to me. E.g.
* Create an error and add additional explanation:
- * error_setg(&err, "invalid quark");
- * error_append_hint(&err, "Valid quarks are up, down, strange, "
+ * error_setg(errp, "invalid quark");
+ * error_append_hint(errp, "Valid quarks are up, down, strange, "
* "charm, top, bottom.\n");
is actually bad advice until ERRP_AUTO_PROPAGATE() turns it into good
advice. I think I'll drop it from my commit, then see how I like the
comment with yours applied.
> + *
> + * In rare cases, we need to pass existing Error object to the caller by hand:
> + * error_propagate(errp, err);
Out of curiosity: can you describe such a case?
> + *
> + * Pass an existing error to the caller with the message modified:
> + * error_propagate_prepend(errp, err);
> + *
> + *
> * Call a function ignoring errors:
> * foo(arg, NULL);
> *
> @@ -104,26 +167,6 @@
> * Call a function treating errors as fatal:
> * foo(arg, &error_fatal);
> *
> - * Receive an error and pass it on to the caller:
> - * Error *err = NULL;
> - * foo(arg, &err);
> - * if (err) {
> - * handle the error...
> - * error_propagate(errp, err);
> - * }
> - * where Error **errp is a parameter, by convention the last one.
> - *
> - * Do *not* "optimize" this to
> - * foo(arg, errp);
> - * if (*errp) { // WRONG!
> - * handle the error...
> - * }
> - * because errp may be NULL!
> - *
> - * But when all you do with the error is pass it on, please use
> - * foo(arg, errp);
> - * for readability.
> - *
> * Receive and accumulate multiple errors (first one wins):
> * Error *err = NULL, *local_err = NULL;
> * foo(arg, &err);
> @@ -151,6 +194,61 @@
> * error_setg(&err, ...); // WRONG!
> * }
> * because this may pass a non-null err to error_setg().
> + *
> + * DEPRECATED*
> + *
> + * The following pattern of receiving, checking, and then forwarding an error
> + * to the caller by hand is now deprecated:
> + *
> + * Error *err = NULL;
> + * foo(arg, &err);
> + * if (err) {
> + * handle the error...
> + * error_propagate(errp, err);
> + * }
> + *
> + * Instead, use ERRP_AUTO_PROPAGATE macro.
> + *
> + * The old pattern is deprecated because of two things:
> + *
> + * 1. Issue with error_abort and error_propagate: when we wrap error_abort by
> + * local_err+error_propagate, the resulting coredump will refer to
> + * error_propagate and not to the place where error happened.
> + *
> + * 2. A lot of extra code of the same pattern
> + *
> + * How to update old code to use ERRP_AUTO_PROPAGATE?
> + *
> + * All you need is to add ERRP_AUTO_PROPAGATE() invocation at function start,
> + * than you may safely dereference errp to check errors and do not need any
> + * additional local Error variables or calls to error_propagate().
> + *
> + * Example:
> + *
> + * old code
> + *
> + * void fn(..., Error **errp) {
> + * Error *err = NULL;
> + * foo(arg, &err);
> + * if (err) {
> + * handle the error...
> + * error_propagate(errp, err);
> + * return;
> + * }
> + * ...
> + * }
> + *
> + * updated code
> + *
> + * void fn(..., Error **errp) {
> + * ERRP_AUTO_PROPAGATE();
> + * foo(arg, errp);
> + * if (*errp) {
> + * handle the error...
> + * return;
> + * }
> + * ...
> + * }
This is another spot where we need to merge your work with mine
properly. When foo() returns a distinct error value, then checking that
is even better:
void fn(..., Error **errp)
{
if (!foo(arg, errp)) {
handle the error...
return;
}
...
}
> */
>
> #ifndef ERROR_H
> @@ -359,6 +457,47 @@ void error_set_internal(Error **errp,
> ErrorClass err_class, const char *fmt, ...)
> GCC_FMT_ATTR(6, 7);
>
The ERRP_AUTO_PROPAGATE stuff starts rather abruptly. I'm afraid an
unprepared reader will get what's going on only at
G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC(), or even at #define
ERRP_AUTO_PROPAGATE().
Let's move the typedef, helper function and macro invocation behind the
definition of ERRP_AUTO_PROPAGATE(), similar to how we declare each
error_FOO_internal() helper function right after the macro that needs
it.
> +typedef struct ErrorPropagator {
> + Error *local_err;
> + Error **errp;
> +} ErrorPropagator;
> +
> +static inline void error_propagator_cleanup(ErrorPropagator *prop)
> +{
> + error_propagate(prop->errp, prop->local_err);
> +}
> +
> +G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC(ErrorPropagator, error_propagator_cleanup);
> +
> +/*
> + * ERRP_AUTO_PROPAGATE
> + *
No other definition comment in this file repeats the name being defined.
Let's keep the comment style locally consistent.
> + * This macro exists to assist with proper error handling in a function which
> + * uses an Error **errp parameter. It must be used as the first line of a
> + * function which modifies an error (with error_prepend, error_append_hint, or
> + * similar) or which wants to dereference *errp. It is still safe (but
> + * useless) to use in other functions.
> + *
> + * If errp is NULL or points to error_fatal, it is rewritten to point to a
> + * local Error object, which will be automatically propagated to the original
> + * errp on function exit (see error_propagator_cleanup).
> + *
> + * After invocation of this macro it is always safe to dereference errp
> + * (as it's not NULL anymore) and to add information by error_prepend or
> + * error_append_hint (as, if it was error_fatal, we swapped it with a
> + * local_error to be propagated on cleanup).
> + *
> + * Note: we don't wrap the error_abort case, as we want resulting coredump
> + * to point to the place where the error happened, not to error_propagate.
> + */
> +#define ERRP_AUTO_PROPAGATE() \
> + g_auto(ErrorPropagator) _auto_errp_prop = {.errp = errp}; \
> + do { \
> + if (!errp || errp == &error_fatal) { \
> + errp = &_auto_errp_prop.local_err; \
> + } \
> + } while (0)
> +
Let's align the backslashes for consistency with nearby macros:
#define ERRP_AUTO_PROPAGATE() \
g_auto(ErrorPropagator) _auto_errp_prop = {.errp = errp}; \
do { \
if (!errp || errp == &error_fatal) { \
errp = &_auto_errp_prop.local_err; \
} \
} while (0)
> /*
> * Special error destination to abort on error.
> * See error_setg() and error_propagate() for details.
^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH v11 8/8] xen: introduce ERRP_AUTO_PROPAGATE
2020-07-04 16:36 ` Philippe Mathieu-Daudé
@ 2020-07-06 7:41 ` Markus Armbruster
2020-07-06 7:55 ` Vladimir Sementsov-Ogievskiy
1 sibling, 0 replies; 16+ messages in thread
From: Markus Armbruster @ 2020-07-06 7:41 UTC (permalink / raw)
To: Philippe Mathieu-Daudé
Cc: Kevin Wolf, Vladimir Sementsov-Ogievskiy, qemu-block,
Paul Durrant, qemu-devel, groug, Stefano Stabellini,
Stefan Hajnoczi, Anthony Perard, xen-devel, Max Reitz
Philippe Mathieu-Daudé <philmd@redhat.com> writes:
> On 7/3/20 11:08 AM, Vladimir Sementsov-Ogievskiy wrote:
>> If we want to add some info to errp (by error_prepend() or
>> error_append_hint()), we must use the ERRP_AUTO_PROPAGATE macro.
>> Otherwise, this info will not be added when errp == &error_fatal
>> (the program will exit prior to the error_append_hint() or
>> error_prepend() call). Fix such cases.
>>
>> If we want to check error after errp-function call, we need to
>> introduce local_err and then propagate it to errp. Instead, use
>> ERRP_AUTO_PROPAGATE macro, benefits are:
>> 1. No need of explicit error_propagate call
>> 2. No need of explicit local_err variable: use errp directly
>> 3. ERRP_AUTO_PROPAGATE leaves errp as is if it's not NULL or
>> &error_fatal, this means that we don't break error_abort
>> (we'll abort on error_set, not on error_propagate)
>>
>> This commit is generated by command
>>
>> sed -n '/^X86 Xen CPUs$/,/^$/{s/^F: //p}' MAINTAINERS | \
>> xargs git ls-files | grep '\.[hc]$' | \
>> xargs spatch \
>> --sp-file scripts/coccinelle/auto-propagated-errp.cocci \
>> --macro-file scripts/cocci-macro-file.h \
>> --in-place --no-show-diff --max-width 80
>>
>> Reported-by: Kevin Wolf <kwolf@redhat.com>
>> Reported-by: Greg Kurz <groug@kaod.org>
>> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
>> ---
>> hw/block/dataplane/xen-block.c | 17 +++---
>> hw/block/xen-block.c | 102 ++++++++++++++-------------------
>> hw/pci-host/xen_igd_pt.c | 7 +--
>> hw/xen/xen-backend.c | 7 +--
>> hw/xen/xen-bus.c | 92 +++++++++++++----------------
>> hw/xen/xen-host-pci-device.c | 27 +++++----
>> hw/xen/xen_pt.c | 25 ++++----
>> hw/xen/xen_pt_config_init.c | 17 +++---
>> 8 files changed, 128 insertions(+), 166 deletions(-)
>
> Without the description, this patch has 800 lines of diff...
> It killed me, I don't have the energy to review patch #7 of this
> series after that, sorry.
> Consider splitting such mechanical patches next time. Here it
> could have been hw/block, hw/pci-host, hw/xen.
Probably my fault; I asked for less fine-grained splitting.
Finding a split of a tree-wide transformation that pleases everyone is
basically impossible.
The conversion to ERRP_AUTO_PROPAGATE() could be one patch per function,
but that would be excessive.
Vladimir chose to split along maintenance boundaries, so he can cc: the
right people on the right code. I agree with the idea. The difficulty
is which boundaries. Our code is not partitioned into maintenance
domains. Instead, we have overlapping sets. Makes sense, because it
mirrors how we actually maintain it.
Because of that, a blind split guided by MAINTAINERS won't work well. A
split that makes sense needs a bit of human judgement, too.
This part makes perfect sense to me from the cc: point of view: it's
Xen, the whole of Xen, and nothing but Xen.
I acknowledge that its size made it exhausting for you to review. I
didn't expect that, probably because after having spent hours on
reviewing and improving the macro and the Coccinelle script, I know
exactly what to look for, and also consider the script trustworthy[*].
> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Thank you, much appreciated!
[*] I've learned not to trust Coccinelle 100%, ever.
^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH v11 8/8] xen: introduce ERRP_AUTO_PROPAGATE
2020-07-04 16:36 ` Philippe Mathieu-Daudé
2020-07-06 7:41 ` Markus Armbruster
@ 2020-07-06 7:55 ` Vladimir Sementsov-Ogievskiy
1 sibling, 0 replies; 16+ messages in thread
From: Vladimir Sementsov-Ogievskiy @ 2020-07-06 7:55 UTC (permalink / raw)
To: Philippe Mathieu-Daudé, qemu-devel
Cc: Kevin Wolf, Stefano Stabellini, qemu-block, Paul Durrant, groug,
armbru, Stefan Hajnoczi, Anthony Perard, xen-devel, Max Reitz
04.07.2020 19:36, Philippe Mathieu-Daudé wrote:
> On 7/3/20 11:08 AM, Vladimir Sementsov-Ogievskiy wrote:
>> If we want to add some info to errp (by error_prepend() or
>> error_append_hint()), we must use the ERRP_AUTO_PROPAGATE macro.
>> Otherwise, this info will not be added when errp == &error_fatal
>> (the program will exit prior to the error_append_hint() or
>> error_prepend() call). Fix such cases.
>>
>> If we want to check error after errp-function call, we need to
>> introduce local_err and then propagate it to errp. Instead, use
>> ERRP_AUTO_PROPAGATE macro, benefits are:
>> 1. No need of explicit error_propagate call
>> 2. No need of explicit local_err variable: use errp directly
>> 3. ERRP_AUTO_PROPAGATE leaves errp as is if it's not NULL or
>> &error_fatal, this means that we don't break error_abort
>> (we'll abort on error_set, not on error_propagate)
>>
>> This commit is generated by command
>>
>> sed -n '/^X86 Xen CPUs$/,/^$/{s/^F: //p}' MAINTAINERS | \
>> xargs git ls-files | grep '\.[hc]$' | \
>> xargs spatch \
>> --sp-file scripts/coccinelle/auto-propagated-errp.cocci \
>> --macro-file scripts/cocci-macro-file.h \
>> --in-place --no-show-diff --max-width 80
>>
>> Reported-by: Kevin Wolf <kwolf@redhat.com>
>> Reported-by: Greg Kurz <groug@kaod.org>
>> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
>> ---
>> hw/block/dataplane/xen-block.c | 17 +++---
>> hw/block/xen-block.c | 102 ++++++++++++++-------------------
>> hw/pci-host/xen_igd_pt.c | 7 +--
>> hw/xen/xen-backend.c | 7 +--
>> hw/xen/xen-bus.c | 92 +++++++++++++----------------
>> hw/xen/xen-host-pci-device.c | 27 +++++----
>> hw/xen/xen_pt.c | 25 ++++----
>> hw/xen/xen_pt_config_init.c | 17 +++---
>> 8 files changed, 128 insertions(+), 166 deletions(-)
>
> Without the description, this patch has 800 lines of diff...
> It killed me, I don't have the energy to review patch #7 of this
> series after that, sorry.
Sorry for that! I really understand you, take a look at Markus's
"[PATCH v2 00/44] Less clumsy error checking", which I'm trying to review
currently..
Still, the patch exists in such form since
"[RFC v5 000/126] error: auto propagated local_err", where it was reviewed
by Anthony, and I suggested to split it, but it was not needed.
Unfortunately, I've dropped r-bs due to changes..
> Consider splitting such mechanical patches next time. Here it
> could have been hw/block, hw/pci-host, hw/xen.
>
> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
>
Thanks a lot!
--
Best regards,
Vladimir
^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH v11 7/8] nbd: introduce ERRP_AUTO_PROPAGATE
2020-07-03 9:08 ` [PATCH v11 7/8] nbd: " Vladimir Sementsov-Ogievskiy
2020-07-06 5:22 ` Markus Armbruster
@ 2020-07-07 11:51 ` Markus Armbruster
1 sibling, 0 replies; 16+ messages in thread
From: Markus Armbruster @ 2020-07-07 11:51 UTC (permalink / raw)
To: Vladimir Sementsov-Ogievskiy
Cc: Kevin Wolf, groug, qemu-devel, qemu-block, Max Reitz
Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> writes:
> If we want to add some info to errp (by error_prepend() or
> error_append_hint()), we must use the ERRP_AUTO_PROPAGATE macro.
> Otherwise, this info will not be added when errp == &error_fatal
Same for &error_abort, but to fix that, ERRP_AUTO_PROPAGATE() would have
to compromise stack backtraces, so it doesn't.
> (the program will exit prior to the error_append_hint() or
> error_prepend() call). Fix such cases.
Unclear what exactly is being fixed here, if anything. What are the
cases? Can they happen?
The following look like possible cases: nbd_read(),
nbd_send_option_request(), nbd_handle_reply_err(), nbd_opt_info_or_go(),
nbd_start_negotiate(), nbd_receive_negotiate(),
nbd_negotiate_send_rep_verr(), nbd_negotiate_send_rep_list(),
nbd_negotiate_handle_export_name(), nbd_negotiate(),
nbd_export_remove().
Additionally in PATCH 6, v9fs_device_realize_common().
Nothing in PATCH 3+4+5+8 as far as I can tell.
If we lack the time to provide a complete assessment in the commit
messages, let's say so there.
> If we want to check error after errp-function call, we need to
> introduce local_err and then propagate it to errp. Instead, use
> ERRP_AUTO_PROPAGATE macro, benefits are:
> 1. No need of explicit error_propagate call
> 2. No need of explicit local_err variable: use errp directly
> 3. ERRP_AUTO_PROPAGATE leaves errp as is if it's not NULL or
> &error_fatal, this means that we don't break error_abort
> (we'll abort on error_set, not on error_propagate)
Direct use of @errp improves behavior when the argument is
&error_abort. Worth mentioning, I think.
>
> This commit is generated by command
>
> sed -n '/^Network Block Device (NBD)$/,/^$/{s/^F: //p}' \
> MAINTAINERS | \
> xargs git ls-files | grep '\.[hc]$' | \
> xargs spatch \
> --sp-file scripts/coccinelle/auto-propagated-errp.cocci \
> --macro-file scripts/cocci-macro-file.h \
> --in-place --no-show-diff --max-width 80
>
> Reported-by: Kevin Wolf <kwolf@redhat.com>
> Reported-by: Greg Kurz <groug@kaod.org>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
^ permalink raw reply [flat|nested] 16+ messages in thread
end of thread, other threads:[~2020-07-07 11:51 UTC | newest]
Thread overview: 16+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-07-03 9:08 [PATCH v11 0/8] error: auto propagated local_err part I Vladimir Sementsov-Ogievskiy
2020-07-03 9:08 ` [PATCH v11 1/8] error: auto propagated local_err Vladimir Sementsov-Ogievskiy
2020-07-06 5:59 ` Markus Armbruster
2020-07-03 9:08 ` [PATCH v11 2/8] scripts: Coccinelle script to use ERRP_AUTO_PROPAGATE() Vladimir Sementsov-Ogievskiy
2020-07-03 9:08 ` [PATCH v11 3/8] SD (Secure Card): introduce ERRP_AUTO_PROPAGATE Vladimir Sementsov-Ogievskiy
2020-07-04 16:28 ` Philippe Mathieu-Daudé
2020-07-03 9:08 ` [PATCH v11 4/8] pflash: " Vladimir Sementsov-Ogievskiy
2020-07-03 9:08 ` [PATCH v11 5/8] fw_cfg: " Vladimir Sementsov-Ogievskiy
2020-07-03 9:08 ` [PATCH v11 6/8] virtio-9p: " Vladimir Sementsov-Ogievskiy
2020-07-03 9:08 ` [PATCH v11 7/8] nbd: " Vladimir Sementsov-Ogievskiy
2020-07-06 5:22 ` Markus Armbruster
2020-07-07 11:51 ` Markus Armbruster
2020-07-03 9:08 ` [PATCH v11 8/8] xen: " Vladimir Sementsov-Ogievskiy
2020-07-04 16:36 ` Philippe Mathieu-Daudé
2020-07-06 7:41 ` Markus Armbruster
2020-07-06 7:55 ` Vladimir Sementsov-Ogievskiy
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