On 12/04/2017 07:55 PM, Andrey Ryabinin wrote: > > > On 12/04/2017 07:42 PM, Christoph Hellwig wrote: >> I don't think we are using alloca in kernel mode code, and we shouldn't. >> What do I miss? Is this hidden support for on-stack VLAs? I thought >> we'd get rid of them as well. >> > > Yes, this is for on-stack VLA. Last time I checked, we still had a few. > E.g. building with -Wvla: /home/andrew/linux/sound/core/pcm_native.c: In function ‘constrain_params_by_rules’: /home/andrew/linux/sound/core/pcm_native.c:326:2: warning: ISO C90 forbids variable length array ‘rstamps’ [-Wvla] unsigned int rstamps[constrs->rules_num]; ^~~~~~~~ In file included from /home/andrew/linux/crypto/cbc.c:14:0: /home/andrew/linux/include/crypto/cbc.h: In function ‘crypto_cbc_decrypt_inplace’: /home/andrew/linux/include/crypto/cbc.h:116:2: warning: ISO C90 forbids variable length array ‘last_iv’ [-Wvla] u8 last_iv[bsize]; ^~ /home/andrew/linux/crypto/pcbc.c: In function ‘crypto_pcbc_encrypt_inplace’: /home/andrew/linux/crypto/pcbc.c:75:2: warning: ISO C90 forbids variable length array ‘tmpbuf’ [-Wvla] u8 tmpbuf[bsize]; ^~ /home/andrew/linux/crypto/pcbc.c: In function ‘crypto_pcbc_decrypt_inplace’: /home/andrew/linux/crypto/pcbc.c:147:2: warning: ISO C90 forbids variable length array ‘tmpbuf’ [-Wvla] u8 tmpbuf[bsize] __aligned(__alignof__(u32)); ^~ /home/andrew/linux/crypto/cts.c: In function ‘cts_cbc_encrypt’: /home/andrew/linux/crypto/cts.c:107:2: warning: ISO C90 forbids variable length array ‘d’ [-Wvla] u8 d[bsize * 2] __aligned(__alignof__(u32)); ^~ /home/andrew/linux/crypto/cts.c: In function ‘cts_cbc_decrypt’: /home/andrew/linux/crypto/cts.c:186:2: warning: ISO C90 forbids variable length array ‘d’ [-Wvla] u8 d[bsize * 2] __aligned(__alignof__(u32)); ^~ /home/andrew/linux/crypto/ctr.c: In function ‘crypto_ctr_crypt_final’: /home/andrew/linux/crypto/ctr.c:61:2: warning: ISO C90 forbids variable length array ‘tmp’ [-Wvla] u8 tmp[bsize + alignmask]; ^~ /home/andrew/linux/crypto/ctr.c: In function ‘crypto_ctr_crypt_inplace’: /home/andrew/linux/crypto/ctr.c:109:2: warning: ISO C90 forbids variable length array ‘tmp’ [-Wvla] u8 tmp[bsize + alignmask]; -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
