Hello,

New build issue found on stable-rc/linux-6.1.y:

--- variable 'is_redirect' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized] in net/sched/act_mirred.o (net/sched/act_mirred.c) [logspec:kbuild,kbuild.compiler.error] ---

- dashboard: https://d.kernelci.org/i/maestro:596e739df5636c4348e4b5c1e97cb3db2187b60e - giturl: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git - commit HEAD: 75ae2fb1c96adec2e5c35ad91b692a4e940c9edc

Log excerpt: ===================================================== net/sched/act_mirred.c:265:6: error: variable 'is_redirect' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized] 265 | if (unlikely(!(dev->flags & IFF_UP)) || !netif_carrier_ok(dev)) { | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ./include/linux/compiler.h:78:22: note: expanded from macro 'unlikely' 78 | # define unlikely(x) __builtin_expect(!!(x), 0) | ^ net/sched/act_mirred.c:331:6: note: uninitialized use occurs here 331 | if (is_redirect) | ^~~~~~~~~~~ net/sched/act_mirred.c:265:2: note: remove the 'if' if its condition is always false 265 | if (unlikely(!(dev->flags & IFF_UP)) || !netif_carrier_ok(dev)) { | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 266 | net_notice_ratelimited("tc mirred to Houston: device %s is down\n", | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 267 | dev->name); | ~~~~~~~~~~~ 268 | goto err_cant_do; | ~~~~~~~~~~~~~~~~~ 269 | } | ~ net/sched/act_mirred.c:265:6: error: variable 'is_redirect' is used uninitialized whenever '||' condition is true [-Werror,-Wsometimes-uninitialized] 265 | if (unlikely(!(dev->flags & IFF_UP)) || !netif_carrier_ok(dev)) { | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ./include/linux/compiler.h:78:22: note: expanded from macro 'unlikely' 78 | # define unlikely(x) __builtin_expect(!!(x), 0) | ^~~~~~~~~~~~~~~~~~~~~~~~~~ net/sched/act_mirred.c:331:6: note: uninitialized use occurs here 331 | if (is_redirect) | ^~~~~~~~~~~ net/sched/act_mirred.c:265:6: note: remove the '||' if its condition is always false 265 | if (unlikely(!(dev->flags & IFF_UP)) || !netif_carrier_ok(dev)) { | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ./include/linux/compiler.h:78:22: note: expanded from macro 'unlikely' 78 | # define unlikely(x) __builtin_expect(!!(x), 0) | ^ net/sched/act_mirred.c:260:6: error: variable 'is_redirect' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized] 260 | if (unlikely(!dev)) { | ^~~~~~~~~~~~~~ ./include/linux/compiler.h:78:22: note: expanded from macro 'unlikely' 78 | # define unlikely(x) __builtin_expect(!!(x), 0) | ^~~~~~~~~~~~~~~~~~~~~~~~~~ net/sched/act_mirred.c:331:6: note: uninitialized use occurs here 331 | if (is_redirect) | ^~~~~~~~~~~ net/sched/act_mirred.c:260:2: note: remove the 'if' if its condition is always false 260 | if (unlikely(!dev)) { | ^~~~~~~~~~~~~~~~~~~~~ 261 | pr_notice_once("tc mirred: target device is gone\n"); | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 262 | goto err_cant_do; | ~~~~~~~~~~~~~~~~~ 263 | } | ~ net/sched/act_mirred.c:238:18: note: initialize the variable 'is_redirect' to silence this warning 238 | bool is_redirect; | ^ | = 0 3 errors generated.

=====================================================

# Builds where the incident occurred:

## defconfig+allmodconfig on (arm64): - compiler: clang-17 - dashboard: https://d.kernelci.org/build/maestro:6807ae9243948caad94dcfbb

## defconfig+allmodconfig+CONFIG_FRAME_WARN=2048 on (arm): - compiler: clang-17 - dashboard: https://d.kernelci.org/build/maestro:6807ae8e43948caad94dcfb8

## i386_defconfig+allmodconfig+CONFIG_FRAME_WARN=2048 on (i386): - compiler: clang-17 - dashboard: https://d.kernelci.org/build/maestro:6807aed943948caad94dcfee

#kernelci issue maestro:596e739df5636c4348e4b5c1e97cb3db2187b60e

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