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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-Reinject: loops=2 maxloops=12 X-Proofpoint-GUID: EE_WTIvePXvXV0R-X_Ii85cZQA63lFue X-Authority-Analysis: v=2.4 cv=KslAGGWN c=1 sm=1 tr=0 ts=69ce935c cx=c_pps a=3Bg1Hr4SwmMryq2xdFQyZA==:117 a=3Bg1Hr4SwmMryq2xdFQyZA==:17 a=IkcTkHD0fZMA:10 a=A5OVakUREuEA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=uAbxVGIbfxUO_5tXvNgY:22 a=VnNF1IyMAAAA:8 a=XyCmtHQiREEm-KVZo3UA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNDAyMDE0MiBTYWx0ZWRfX8gsYTM+8UAcv f0/wueSUmdQ1N6/9gzMtRyQDK60mw8O2RMeDlpWhiemm2lJY7x2gIpl/ri9+dZ3v84Ysn56pitF k+GKq5CGtvM00RWH/iNqybcFWrLZI1u4bwN/WrWHcbkaPpMGEkc3OqHhYHMkf5p/TZ1FhHWeYLq e1mXcGsTM915SGsCHYfH6HbGF11xO29QllhLInGG3s4RUa6lqF6c3t9FME4zhetDlzUprXBN6pe U38Q6pPT539+9m/b0KCU38cLO2ZhLCrUKh9/7HrzKTBZ1+YxqphgGg9P8E8xseqsJkm0T4kiiO5 i69QJbVonnfLEy7Axt3WuC91pxAQPo5cSElKn84pLdeq55oj2qbZ3fzb1rYtRJow79gvSlptVUO EYnP/ji7p8cGaMqZVeBc7tjXzHOouehx8SygwQzeo7JzXuFqImJuIccVsW4VN0wc8O53aIFzh9w 4GiJjpYNJJCoX8mxyuQ== X-Proofpoint-ORIG-GUID: Dg1k1KckGNmFoIGhYUd_YRKeJOefvVvn X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-04-02_02,2026-04-02_03,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 lowpriorityscore=0 priorityscore=1501 suspectscore=0 phishscore=0 adultscore=0 bulkscore=0 impostorscore=0 clxscore=1011 spamscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2603050001 definitions=main-2604020142 On 30/03/26 4:05 pm, Venkat Rao Bagalkote wrote: > The global nvram_mutex in drivers/char/nvram.c is redundant and unused, > and this triggers compiler warnings on some configurations. > > All platform-specific nvram operations already provide their own internal > synchronization, meaning the wrapper-level mutex does not provide any > additional safety. > > Remove the nvram_mutex definition along with all remaining lock/unlock > users across PPC32, x86, and m68k code paths, and rely entirely on the > per-architecture nvram implementations for locking. > > Suggested-by: Arnd Bergmann > Signed-off-by: Venkat Rao Bagalkote > --- Without Fix =============== make -j 33 -s && make modules_install && make install In file included from ./include/linux/seqlock.h:20,                  from ./include/linux/mmzone.h:17,                  from ./include/linux/gfp.h:7,                  from ./include/linux/umh.h:4,                  from ./include/linux/kmod.h:9,                  from ./include/linux/module.h:18,                  from drivers/char/nvram.c:34: drivers/char/nvram.c:56:21: warning: 'nvram_mutex' defined but not used [-Wunused-variable]    56 | static DEFINE_MUTEX(nvram_mutex);       |                     ^~~~~~~~~~~ ./include/linux/mutex.h:87:22: note: in definition of macro 'DEFINE_MUTEX'    87 |         struct mutex mutexname = __MUTEX_INITIALIZER(mutexname)       |                      ^~~~~~~~~ With this patch issue is fixed Please add below tag yeswanth Thanks, Yeswanth Krishna > v4: > - Remove all remaining nvram_mutex call sites, completing the mutex removal > > v3: > - Removed global nvram_mutex definition > > drivers/char/nvram.c | 16 +++------------- > 1 file changed, 3 insertions(+), 13 deletions(-) > > diff --git a/drivers/char/nvram.c b/drivers/char/nvram.c > index 9eff426a9286..e89cc1f1c89e 100644 > --- a/drivers/char/nvram.c > +++ b/drivers/char/nvram.c > @@ -53,7 +53,6 @@ > #include > #endif > > -static DEFINE_MUTEX(nvram_mutex); > static DEFINE_SPINLOCK(nvram_state_lock); > static int nvram_open_cnt; /* #times opened */ > static int nvram_open_mode; /* special open modes */ > @@ -310,11 +309,8 @@ static long nvram_misc_ioctl(struct file *file, unsigned int cmd, > break; > #ifdef CONFIG_PPC32 > case IOC_NVRAM_SYNC: > - if (ppc_md.nvram_sync != NULL) { > - mutex_lock(&nvram_mutex); > + if (ppc_md.nvram_sync) > ppc_md.nvram_sync(); > - mutex_unlock(&nvram_mutex); > - } > ret = 0; > break; > #endif > @@ -324,11 +320,8 @@ static long nvram_misc_ioctl(struct file *file, unsigned int cmd, > if (!capable(CAP_SYS_ADMIN)) > return -EACCES; > > - if (arch_nvram_ops.initialize != NULL) { > - mutex_lock(&nvram_mutex); > + if (arch_nvram_ops.initialize) > ret = arch_nvram_ops.initialize(); > - mutex_unlock(&nvram_mutex); > - } > break; > case NVRAM_SETCKS: > /* just set checksum, contents unchanged (maybe useful after > @@ -336,11 +329,8 @@ static long nvram_misc_ioctl(struct file *file, unsigned int cmd, > if (!capable(CAP_SYS_ADMIN)) > return -EACCES; > > - if (arch_nvram_ops.set_checksum != NULL) { > - mutex_lock(&nvram_mutex); > + if (arch_nvram_ops.set_checksum) > ret = arch_nvram_ops.set_checksum(); > - mutex_unlock(&nvram_mutex); > - } > break; > #endif /* CONFIG_X86 || CONFIG_M68K */ > }