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Tsirkin" , Jason Wang , Xuan Zhuo , Eugenio =?iso-8859-1?Q?P=E9rez?= , Vivek Goyal , Dave Young , Thomas Huth , Cornelia Huck , Janosch Frank , Claudio Imbrenda , Eric Farman , Andrew Morton Subject: Re: [PATCH v1 02/11] fs/proc/vmcore: replace vmcoredd_mutex by vmcore_mutex Message-ID: References: <20241025151134.1275575-1-david@redhat.com> <20241025151134.1275575-3-david@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241025151134.1275575-3-david@redhat.com> X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 X-Rspam-User: X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 2EA621A0006 X-Stat-Signature: tafe93hf8ixi61xww6zjq6urs9xfg5kt X-HE-Tag: 1731663087-321577 X-HE-Meta: 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 qz71fXeI AEgj4SmHz9LLsZ7A6wXgh2drwL8nI4m/vV+6POTBv/r7G+LlPzgh4TJEUuZd8kh599FO98ZXHOlgcHC9xdKyd63DaWRxxvgNPqKOoXdVeiLXQrOoUEmiCH2hw+EhhpVHkWaAdK0QnibpOu+Wt3hPebPLzuY4oC9EvYImlhA58e9lCGSZPTjks1E2Ml8ozRs27meEPnQfMC+jkK4RXGNeoehLpybqAaYodpkqhrmHqIVeZ1B6uHIajj844G3Ux7Za6je/StJLRZlMmHLnWHbbAjFE6n6d7ED+3q94a3e2nfHTgsu2QCbZ5K9gC/lbkaF2WtJOzlesedIxT7GdhX6tVQWwGwqpnUlOUCwKuI3kfBZR1yCyN7141dohpV9y6pGFWI4QVTR3Th31W7THdx4s4Db58gf+mWYfIfJRshW76M6QYYAU= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 10/25/24 at 05:11pm, David Hildenbrand wrote: > Let's use our new mutex instead. Is there reason vmcoredd_mutex need be replaced and integrated with the vmcore_mutex? Is it the reason the concurrent opening of vmcore could happen with the old vmcoredd_mutex? > > Signed-off-by: David Hildenbrand > --- > fs/proc/vmcore.c | 17 ++++++++--------- > 1 file changed, 8 insertions(+), 9 deletions(-) > > diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c > index 110ce193d20f..b91c304463c9 100644 > --- a/fs/proc/vmcore.c > +++ b/fs/proc/vmcore.c > @@ -53,7 +53,6 @@ static struct proc_dir_entry *proc_vmcore; > #ifdef CONFIG_PROC_VMCORE_DEVICE_DUMP > /* Device Dump list and mutex to synchronize access to list */ > static LIST_HEAD(vmcoredd_list); > -static DEFINE_MUTEX(vmcoredd_mutex); > > static bool vmcoredd_disabled; > core_param(novmcoredd, vmcoredd_disabled, bool, 0); > @@ -248,7 +247,7 @@ static int vmcoredd_copy_dumps(struct iov_iter *iter, u64 start, size_t size) > size_t tsz; > char *buf; > > - mutex_lock(&vmcoredd_mutex); > + mutex_lock(&vmcore_mutex); > list_for_each_entry(dump, &vmcoredd_list, list) { > if (start < offset + dump->size) { > tsz = min(offset + (u64)dump->size - start, (u64)size); > @@ -269,7 +268,7 @@ static int vmcoredd_copy_dumps(struct iov_iter *iter, u64 start, size_t size) > } > > out_unlock: > - mutex_unlock(&vmcoredd_mutex); > + mutex_unlock(&vmcore_mutex); > return ret; > } > > @@ -283,7 +282,7 @@ static int vmcoredd_mmap_dumps(struct vm_area_struct *vma, unsigned long dst, > size_t tsz; > char *buf; > > - mutex_lock(&vmcoredd_mutex); > + mutex_lock(&vmcore_mutex); > list_for_each_entry(dump, &vmcoredd_list, list) { > if (start < offset + dump->size) { > tsz = min(offset + (u64)dump->size - start, (u64)size); > @@ -306,7 +305,7 @@ static int vmcoredd_mmap_dumps(struct vm_area_struct *vma, unsigned long dst, > } > > out_unlock: > - mutex_unlock(&vmcoredd_mutex); > + mutex_unlock(&vmcore_mutex); > return ret; > } > #endif /* CONFIG_MMU */ > @@ -1517,9 +1516,9 @@ int vmcore_add_device_dump(struct vmcoredd_data *data) > dump->size = data_size; > > /* Add the dump to driver sysfs list */ > - mutex_lock(&vmcoredd_mutex); > + mutex_lock(&vmcore_mutex); > list_add_tail(&dump->list, &vmcoredd_list); > - mutex_unlock(&vmcoredd_mutex); > + mutex_unlock(&vmcore_mutex); > > vmcoredd_update_size(data_size); > return 0; > @@ -1537,7 +1536,7 @@ EXPORT_SYMBOL(vmcore_add_device_dump); > static void vmcore_free_device_dumps(void) > { > #ifdef CONFIG_PROC_VMCORE_DEVICE_DUMP > - mutex_lock(&vmcoredd_mutex); > + mutex_lock(&vmcore_mutex); > while (!list_empty(&vmcoredd_list)) { > struct vmcoredd_node *dump; > > @@ -1547,7 +1546,7 @@ static void vmcore_free_device_dumps(void) > vfree(dump->buf); > vfree(dump); > } > - mutex_unlock(&vmcoredd_mutex); > + mutex_unlock(&vmcore_mutex); > #endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */ > } > > -- > 2.46.1 >