From: kernel test robot <lkp@intel.com>
To: kbuild@lists.01.org
Subject: [ammarfaizi2-block:google/android/kernel/common/android13-5.15 5109/5372] drivers/iommu/iova.c:364:3: warning: Value stored to 'candidate_gap' is never read [clang-analyzer-deadcode.DeadStores]
Date: Sat, 19 Mar 2022 12:09:47 +0800 [thread overview]
Message-ID: <202203191211.fcb2dVA5-lkp@intel.com> (raw)
[-- Attachment #1: Type: text/plain, Size: 19857 bytes --]
CC: llvm(a)lists.linux.dev
CC: kbuild-all(a)lists.01.org
BCC: lkp(a)intel.com
CC: "GNU/Weeb Mailing List" <gwml@vger.gnuweeb.org>
CC: linux-kernel(a)vger.kernel.org
TO: Liam Mark <lmark@codeaurora.org>
CC: Todd Kjos <tkjos@google.com>
CC: "Isaac J. Manjarres" <isaacm@codeaurora.org>
CC: Georgi Djakov <quic_c_gdjako@quicinc.com>
tree: https://github.com/ammarfaizi2/linux-block google/android/kernel/common/android13-5.15
head: 28b046777fb6eee7c4382a4272e6fa1f517d7038
commit: 150c882a3dd8f530eb425e8a264838131973a53f [5109/5372] FROMLIST: iommu/iova: Add a best-fit algorithm
:::::: branch date: 21 hours ago
:::::: commit date: 9 days ago
config: x86_64-randconfig-c007 (https://download.01.org/0day-ci/archive/20220319/202203191211.fcb2dVA5-lkp(a)intel.com/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project a6e70e4056dff962ec634c5bd4f2f4105a0bef71)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/ammarfaizi2/linux-block/commit/150c882a3dd8f530eb425e8a264838131973a53f
git remote add ammarfaizi2-block https://github.com/ammarfaizi2/linux-block
git fetch --no-tags ammarfaizi2-block google/android/kernel/common/android13-5.15
git checkout 150c882a3dd8f530eb425e8a264838131973a53f
# save the config file to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 clang-analyzer
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
clang-analyzer warnings: (new ones prefixed by >>)
^
include/asm-generic/rwonce.h:60:2: note: expanded from macro 'WRITE_ONCE'
compiletime_assert_rwonce_type(x); \
^
include/asm-generic/rwonce.h:36:2: note: expanded from macro 'compiletime_assert_rwonce_type'
compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \
^
include/linux/compiler_types.h:322:2: note: expanded from macro 'compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
^
include/linux/compiler_types.h:310:2: note: expanded from macro '_compiletime_assert'
__compiletime_assert(condition, msg, prefix, suffix)
^
include/linux/compiler_types.h:302:3: note: expanded from macro '__compiletime_assert'
if (!(condition)) \
^
include/linux/skbuff.h:1961:2: note: Loop condition is false. Exiting loop
WRITE_ONCE(prev->next, newsk);
^
include/asm-generic/rwonce.h:60:2: note: expanded from macro 'WRITE_ONCE'
compiletime_assert_rwonce_type(x); \
^
include/asm-generic/rwonce.h:36:2: note: expanded from macro 'compiletime_assert_rwonce_type'
compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \
^
include/linux/compiler_types.h:322:2: note: expanded from macro 'compiletime_assert'
_compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
^
include/linux/compiler_types.h:310:2: note: expanded from macro '_compiletime_assert'
__compiletime_assert(condition, msg, prefix, suffix)
^
include/linux/compiler_types.h:300:2: note: expanded from macro '__compiletime_assert'
do { \
^
include/linux/skbuff.h:1961:2: note: Dereference of null pointer
WRITE_ONCE(prev->next, newsk);
^
include/asm-generic/rwonce.h:61:2: note: expanded from macro 'WRITE_ONCE'
__WRITE_ONCE(x, val); \
^~~~~~~~~~~~~~~~~~~~
include/asm-generic/rwonce.h:55:30: note: expanded from macro '__WRITE_ONCE'
*(volatile typeof(x) *)&(x) = (val); \
~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~
include/linux/skbuff.h:2067:2: warning: 2nd function call argument is an uninitialized value [clang-analyzer-core.CallAndMessage]
__skb_insert(newsk, next->prev, next, list);
^
net/tipc/bcast.c:565:2: note: Calling 'tipc_bcbase_xmit'
tipc_bcbase_xmit(net, &xmitq);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
net/tipc/bcast.c:184:2: note: Taking false branch
if (skb_queue_empty(xmitq))
^
net/tipc/bcast.c:189:6: note: Assuming 'bearer_id' is < 0
if (bearer_id >= 0) {
^~~~~~~~~~~~~~
net/tipc/bcast.c:189:2: note: Taking false branch
if (bearer_id >= 0) {
^
net/tipc/bcast.c:195:2: note: Calling '__skb_queue_head_init'
__skb_queue_head_init(&_xmitq);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
net/tipc/bcast.c:195:2: note: Returning from '__skb_queue_head_init'
__skb_queue_head_init(&_xmitq);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
net/tipc/bcast.c:196:2: note: Loop condition is true. Entering loop body
for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) {
^
net/tipc/bcast.c:197:7: note: Assuming the condition is false
if (!bb->dests[bearer_id])
^~~~~~~~~~~~~~~~~~~~~
net/tipc/bcast.c:197:3: note: Taking false branch
if (!bb->dests[bearer_id])
^
net/tipc/bcast.c:200:3: note: Loop condition is true. Entering loop body
skb_queue_walk(xmitq, skb) {
^
include/linux/skbuff.h:3556:3: note: expanded from macro 'skb_queue_walk'
for (skb = (queue)->next; \
^
net/tipc/bcast.c:202:8: note: Assuming '_skb' is non-null
if (!_skb)
^~~~~
net/tipc/bcast.c:202:4: note: Taking false branch
if (!_skb)
^
net/tipc/bcast.c:204:4: note: Calling '__skb_queue_tail'
__skb_queue_tail(&_xmitq, _skb);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/skbuff.h:2100:2: note: Calling '__skb_queue_before'
__skb_queue_before(list, (struct sk_buff *)list, newsk);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/skbuff.h:2067:2: note: 2nd function call argument is an uninitialized value
__skb_insert(newsk, next->prev, next, list);
^ ~~~~~~~~~~
Suppressed 10 warnings (10 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
6 warnings generated.
Suppressed 6 warnings (6 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
5 warnings generated.
>> drivers/iommu/iova.c:364:3: warning: Value stored to 'candidate_gap' is never read [clang-analyzer-deadcode.DeadStores]
candidate_gap = gap;
^ ~~~
drivers/iommu/iova.c:364:3: note: Value stored to 'candidate_gap' is never read
candidate_gap = gap;
^ ~~~
Suppressed 4 warnings (4 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
6 warnings generated.
drivers/gpu/vga/vgaarb.c:235:17: warning: Value stored to 'dev' during its initialization is never read [clang-analyzer-deadcode.DeadStores]
struct device *dev = &vgadev->pdev->dev;
^~~ ~~~~~~~~~~~~~~~~~~
drivers/gpu/vga/vgaarb.c:235:17: note: Value stored to 'dev' during its initialization is never read
struct device *dev = &vgadev->pdev->dev;
^~~ ~~~~~~~~~~~~~~~~~~
drivers/gpu/vga/vgaarb.c:373:17: warning: Value stored to 'dev' during its initialization is never read [clang-analyzer-deadcode.DeadStores]
struct device *dev = &vgadev->pdev->dev;
^~~ ~~~~~~~~~~~~~~~~~~
drivers/gpu/vga/vgaarb.c:373:17: note: Value stored to 'dev' during its initialization is never read
struct device *dev = &vgadev->pdev->dev;
^~~ ~~~~~~~~~~~~~~~~~~
Suppressed 4 warnings (4 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
3 warnings generated.
Suppressed 3 warnings (3 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
9 warnings generated.
Suppressed 9 warnings (9 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
4 warnings generated.
drivers/base/bus.c:873:18: warning: Access to field 'drivers_kset' results in a dereference of a null pointer (loaded from field 'p') [clang-analyzer-core.NullDereference]
kset_unregister(bus->p->drivers_kset);
^
drivers/base/bus.c:1139:9: note: Calling 'subsys_register'
return subsys_register(subsys, groups, &system_kset->kobj);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/base/bus.c:1083:8: note: Calling 'bus_register'
err = bus_register(subsys);
^~~~~~~~~~~~~~~~~~~~
drivers/base/bus.c:788:6: note: Assuming 'priv' is non-null
if (!priv)
^~~~~
drivers/base/bus.c:788:2: note: Taking false branch
if (!priv)
^
drivers/base/bus.c:794:2: note: Loop condition is false. Exiting loop
BLOCKING_INIT_NOTIFIER_HEAD(&priv->bus_notifier);
^
include/linux/notifier.h:85:3: note: expanded from macro 'BLOCKING_INIT_NOTIFIER_HEAD'
init_rwsem(&(name)->rwsem); \
^
include/linux/rwsem.h:123:30: note: expanded from macro 'init_rwsem'
#define init_rwsem(sem) \
^
drivers/base/bus.c:794:2: note: Loop condition is false. Exiting loop
BLOCKING_INIT_NOTIFIER_HEAD(&priv->bus_notifier);
^
include/linux/notifier.h:84:43: note: expanded from macro 'BLOCKING_INIT_NOTIFIER_HEAD'
#define BLOCKING_INIT_NOTIFIER_HEAD(name) do { \
^
drivers/base/bus.c:797:6: note: Assuming 'retval' is not equal to 0
if (retval)
^~~~~~
drivers/base/bus.c:797:2: note: Taking true branch
if (retval)
^
drivers/base/bus.c:798:3: note: Control jumps to line 853
goto out;
^
drivers/base/bus.c:854:2: note: Null pointer value stored to field 'p'
bus->p = NULL;
^~~~~~~~~~~~~
drivers/base/bus.c:1083:8: note: Returning from 'bus_register'
err = bus_register(subsys);
^~~~~~~~~~~~~~~~~~~~
drivers/base/bus.c:1084:6: note: Assuming 'err' is >= 0
if (err < 0)
^~~~~~~
drivers/base/bus.c:1084:2: note: Taking false branch
if (err < 0)
^
drivers/base/bus.c:1088:6: note: Assuming 'dev' is null
if (!dev) {
^~~~
drivers/base/bus.c:1088:2: note: Taking true branch
if (!dev) {
^
drivers/base/bus.c:1090:3: note: Control jumps to line 1114
goto err_dev;
^
drivers/base/bus.c:1114:2: note: Calling 'bus_unregister'
bus_unregister(subsys);
^~~~~~~~~~~~~~~~~~~~~~
drivers/base/bus.c:868:2: note: Taking false branch
pr_debug("bus: '%s': unregistering\n", bus->name);
^
include/linux/printk.h:580:2: note: expanded from macro 'pr_debug'
no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
^
include/linux/printk.h:131:2: note: expanded from macro 'no_printk'
if (0) \
vim +/candidate_gap +364 drivers/iommu/iova.c
f8de50eb6b0855 drivers/pci/iova.c Keshavamurthy, Anil S 2007-10-21 320
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 321 static int __alloc_and_insert_iova_best_fit(struct iova_domain *iovad,
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 322 unsigned long size,
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 323 unsigned long limit_pfn,
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 324 struct iova *new, bool size_aligned)
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 325 {
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 326 struct rb_node *curr, *prev;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 327 struct iova *curr_iova, *prev_iova;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 328 unsigned long flags;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 329 unsigned long align_mask = ~0UL;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 330 struct rb_node *candidate_rb_parent;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 331 unsigned long new_pfn, candidate_pfn = ~0UL;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 332 unsigned long gap, candidate_gap = ~0UL;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 333
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 334 if (size_aligned)
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 335 align_mask <<= limit_align_shift(iovad, fls_long(size - 1));
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 336
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 337 /* Walk the tree backwards */
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 338 spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 339 curr = &iovad->anchor.node;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 340 prev = rb_prev(curr);
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 341 for (; prev; curr = prev, prev = rb_prev(curr)) {
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 342 curr_iova = rb_entry(curr, struct iova, node);
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 343 prev_iova = rb_entry(prev, struct iova, node);
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 344
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 345 limit_pfn = min(limit_pfn, curr_iova->pfn_lo);
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 346 new_pfn = (limit_pfn - size) & align_mask;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 347 gap = curr_iova->pfn_lo - prev_iova->pfn_hi - 1;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 348 if ((limit_pfn >= size) && (new_pfn > prev_iova->pfn_hi)
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 349 && (gap < candidate_gap)) {
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 350 candidate_gap = gap;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 351 candidate_pfn = new_pfn;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 352 candidate_rb_parent = curr;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 353 if (gap == size)
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 354 goto insert;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 355 }
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 356 }
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 357
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 358 curr_iova = rb_entry(curr, struct iova, node);
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 359 limit_pfn = min(limit_pfn, curr_iova->pfn_lo);
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 360 new_pfn = (limit_pfn - size) & align_mask;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 361 gap = curr_iova->pfn_lo - iovad->start_pfn;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 362 if (limit_pfn >= size && new_pfn >= iovad->start_pfn &&
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 363 gap < candidate_gap) {
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 @364 candidate_gap = gap;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 365 candidate_pfn = new_pfn;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 366 candidate_rb_parent = curr;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 367 }
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 368
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 369 insert:
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 370 if (candidate_pfn == ~0UL) {
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 371 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 372 return -ENOMEM;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 373 }
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 374
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 375 /* pfn_lo will point to size aligned address if size_aligned is set */
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 376 new->pfn_lo = candidate_pfn;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 377 new->pfn_hi = new->pfn_lo + size - 1;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 378
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 379 /* If we have 'prev', it's a valid place to start the insertion. */
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 380 iova_insert_rbtree(&iovad->rbroot, new, candidate_rb_parent);
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 381 spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 382 return 0;
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 383 }
150c882a3dd8f5 drivers/iommu/iova.c Liam Mark 2020-02-26 384
---
0-DAY CI Kernel Test Service
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org
reply other threads:[~2022-03-19 4:09 UTC|newest]
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