On Thu, 12 Feb 2009, Sachin P. Sant wrote: > On a powerpc box 2.6.29-rc4-git4 randconfig build fails with : > > CC [M] crypto/async_tx/async_xor.o > crypto/async_tx/async_xor.c: In function async_xor_init: > crypto/async_tx/async_xor.c:313: error: size of array type name is negative > make[2]: *** [crypto/async_tx/async_xor.o] Error 1 > make[1]: *** [crypto/async_tx] Error 2 > make: *** [crypto] Error 2 | static int __init async_xor_init(void) | { | #ifdef CONFIG_DMA_ENGINE | /* To conserve stack space the input src_list (array of page pointers) | * is reused to hold the array of dma addresses passed to the driver. | * This conversion is only possible when dma_addr_t is less than the | * the size of a pointer. HIGHMEM64G is known to violate this | * assumption. | */ | BUILD_BUG_ON(sizeof(dma_addr_t) > sizeof(struct page *)); | #endif | | return 0; | } Of course. This will fail on any 32-bit platform with a physical address space larger than 32-bit (PPC44x, several MIPSes, ...). The offending commit is: commit 0036731c88fdb5bf4f04a796a30b5e445fc57f54 Author: Dan Williams <dan.j.williams@xxxxxxxxx> Date: Sat Feb 2 19:49:57 2008 -0700 async_tx: kill tx_set_src and tx_set_dest methods The tx_set_src and tx_set_dest methods were originally implemented to allow an array of addresses to be passed down from async_xor to the dmaengine driver while minimizing stack overhead. Removing these methods allows drivers to have all transaction parameters available at 'prep' time, saves two function pointers in struct dma_async_tx_descriptor, and reduces the number of indirect branches.. A consequence of moving this data to the 'prep' routine is that multi-source routines like async_xor need temporary storage to convert an array of linear addresses into an array of dma addresses. In order to keep the same stack footprint of the previous implementation the input array is reused as storage for the dma addresses. This requires that sizeof(dma_addr_t) be less than or equal to sizeof(void *). As a consequence CONFIG_DMADEVICES now depends on !CONFIG_HIGHMEM64G. It also requires that drivers be able to make descriptor resources available when the 'prep' routine is polled. Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> Acked-by: Shannon Nelson <shannon.nelson@xxxxxxxxx> With kind regards, Geert Uytterhoeven Software Architect Sony Techsoft Centre Europe The Corporate Village · Da Vincilaan 7-D1 · B-1935 Zaventem · Belgium Phone: +32 (0)2 700 8453 Fax: +32 (0)2 700 8622 E-mail: Geert.Uytterhoeven@xxxxxxxxxxx Internet: http://www.sony-europe.com/ A division of Sony Europe (Belgium) N.V. VAT BE 0413.825.160 · RPR Brussels Fortis · BIC GEBABEBB · IBAN BE41293037680010 -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html