On 2021/6/18 12:09, Steve French wrote:
> I am curious the motivation for these - I agree that removing the
> debug messages saves (albeit trivial amount of) memory but curious
> about how other areas of the kernel handle logging low memory/out of
> memory issues?
$ scripts/checkpatch.pl --types=OOM_MESSAGE -- $(git ls-files kernel/) > err.txt
$ cat err.txt | grep WARNING | wc -l
12
$ git grep -wn k.alloc kernel/ | wc -l
469
$ git grep -wn kstrdup kernel/ | wc -l
88
... ... Other kernel memory allocation APIs are omitted.
You see, the vast majority are not printed.
>
> On Thu, Jun 17, 2021 at 3:42 AM Zhen Lei <thunder.leizhen@xxxxxxxxxx> wrote:
>>
>> Fixes scripts/checkpatch.pl warning:
>> WARNING: Possible unnecessary 'out of memory' message
>>
>> Remove it can help us save a bit of memory.
>>
>> Signed-off-by: Zhen Lei <thunder.leizhen@xxxxxxxxxx>
>> ---
>> fs/cifs/cifsencrypt.c | 4 +---
>> fs/cifs/connect.c | 6 +-----
>> fs/cifs/sess.c | 6 +-----
>> fs/cifs/smb2pdu.c | 2 --
>> 4 files changed, 3 insertions(+), 15 deletions(-)
>>
>> diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
>> index b8f1ff9a83f3..74f16730e502 100644
>> --- a/fs/cifs/cifsencrypt.c
>> +++ b/fs/cifs/cifsencrypt.c
>> @@ -787,10 +787,8 @@ calc_seckey(struct cifs_ses *ses)
>> get_random_bytes(sec_key, CIFS_SESS_KEY_SIZE);
>>
>> ctx_arc4 = kmalloc(sizeof(*ctx_arc4), GFP_KERNEL);
>> - if (!ctx_arc4) {
>> - cifs_dbg(VFS, "Could not allocate arc4 context\n");
>> + if (!ctx_arc4)
>> return -ENOMEM;
>> - }
>>
>> arc4_setkey(ctx_arc4, ses->auth_key.response, CIFS_SESS_KEY_SIZE);
>> arc4_crypt(ctx_arc4, ses->ntlmssp->ciphertext, sec_key,
>> diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
>> index 05f5c84a63a4..b52bb6dc6ecb 100644
>> --- a/fs/cifs/connect.c
>> +++ b/fs/cifs/connect.c
>> @@ -97,10 +97,8 @@ static int reconn_set_ipaddr_from_hostname(struct TCP_Server_Info *server)
>> len = strlen(server->hostname) + 3;
>>
>> unc = kmalloc(len, GFP_KERNEL);
>> - if (!unc) {
>> - cifs_dbg(FYI, "%s: failed to create UNC path\n", __func__);
>> + if (!unc)
>> return -ENOMEM;
>> - }
>> scnprintf(unc, len, "\\\\%s", server->hostname);
>>
>> rc = dns_resolve_server_name_to_ip(unc, &ipaddr);
>> @@ -1758,8 +1756,6 @@ cifs_set_cifscreds(struct smb3_fs_context *ctx, struct cifs_ses *ses)
>> if (is_domain && ses->domainName) {
>> ctx->domainname = kstrdup(ses->domainName, GFP_KERNEL);
>> if (!ctx->domainname) {
>> - cifs_dbg(FYI, "Unable to allocate %zd bytes for domain\n",
>> - len);
>> rc = -ENOMEM;
>> kfree(ctx->username);
>> ctx->username = NULL;
>> diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
>> index cd19aa11f27e..cc97b2981c3d 100644
>> --- a/fs/cifs/sess.c
>> +++ b/fs/cifs/sess.c
>> @@ -602,10 +602,8 @@ int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len,
>> if (tilen) {
>> ses->auth_key.response = kmemdup(bcc_ptr + tioffset, tilen,
>> GFP_KERNEL);
>> - if (!ses->auth_key.response) {
>> - cifs_dbg(VFS, "Challenge target info alloc failure\n");
>> + if (!ses->auth_key.response)
>> return -ENOMEM;
>> - }
>> ses->auth_key.len = tilen;
>> }
>>
>> @@ -1338,8 +1336,6 @@ sess_auth_kerberos(struct sess_data *sess_data)
>> ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len,
>> GFP_KERNEL);
>> if (!ses->auth_key.response) {
>> - cifs_dbg(VFS, "Kerberos can't allocate (%u bytes) memory\n",
>> - msg->sesskey_len);
>> rc = -ENOMEM;
>> goto out_put_spnego_key;
>> }
>> diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
>> index c205f93e0a10..2b978564e188 100644
>> --- a/fs/cifs/smb2pdu.c
>> +++ b/fs/cifs/smb2pdu.c
>> @@ -1355,8 +1355,6 @@ SMB2_auth_kerberos(struct SMB2_sess_data *sess_data)
>> ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len,
>> GFP_KERNEL);
>> if (!ses->auth_key.response) {
>> - cifs_dbg(VFS, "Kerberos can't allocate (%u bytes) memory\n",
>> - msg->sesskey_len);
>> rc = -ENOMEM;
>> goto out_put_spnego_key;
>> }
>> --
>> 2.25.1
>>
>>
>
>
