> From: Cornelia Huck [mailto:[EMAIL PROTECTED] > > On Tue, 15 May 2007 20:19:14 -0700, > Andrew Morton <[EMAIL PROTECTED]> wrote: > > > ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.22- > rc1/2.6.22-rc1-mm1/ > > Doesn't build on s390 when selecting the md menu: > > drivers/built-in.o(.text+0x438ae): In function `async_xor': > : undefined reference to `dma_map_page' > drivers/built-in.o(.text+0x43aac): In function `async_xor': > : undefined reference to `dma_map_page' > drivers/built-in.o(.text+0x43d2e): In function `async_xor_zero_sum': > : undefined reference to `dma_map_page' > drivers/built-in.o(.text+0x43f50): In function `async_memcpy': > : undefined reference to `dma_map_page' > drivers/built-in.o(.text+0x43f90): In function `async_memcpy': > : undefined reference to `dma_map_page' > drivers/built-in.o(.text+0x4423e): more undefined references to > `dma_map_page' follow > > This is caused by the following in drivers/md/Kconfig: > > menuconfig MD > bool "Multiple devices driver support (RAID and LVM)" > depends on BLOCK > select ASYNC_TX_DMA > help > Support multiple physical spindles through a single logical device. > Required for RAID and logical volume management.
The rationale for the 'select' here was to attempt to prevent user confusion since MD_RAID456 now depends on ASYNC_TX_DMA. > > ASYNC_TX_DMA is defined in drivers/dma/Kconfig, which has > > menu "DMA Engine support" > depends on !S390 > > but unfortunately ASYNC_TX_DMA depends neither on the menu nor > on !S390. (I think it was just an unknown symbol on s390 before > Martin's Kconfig rework, so I could build older -mm kernels.) > > Currently, the only md stuff depending on ASYNC_TX_DMA is MD_RAID456 > (which means it doesn't work on s390 anymore, which is bad enough). > With the select statement, no md stuff can be build on s390 at all (and > I really don't see why ASYNC_TX_DMA should be forced upon all md > users)... I agree it should not be forced on all users, I will push the following change: diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig index 4a1b77e..fd29a54 100644 --- a/drivers/md/Kconfig +++ b/drivers/md/Kconfig @@ -8,7 +8,6 @@ menu "Multi-device support (RAID and LVM)" config MD bool "Multiple devices driver support (RAID and LVM)" - select ASYNC_TX_DMA help Support multiple physical spindles through a single logical device. Required for RAID and logical volume management. @@ -109,7 +108,8 @@ config MD_RAID10 config MD_RAID456 tristate "RAID-4/RAID-5/RAID-6 mode" - depends on BLK_DEV_MD && ASYNC_TX_DMA + depends on BLK_DEV_MD + select ASYNC_TX_DMA ---help--- A RAID-5 set of N drives with a capacity of C MB per drive provides the capacity of C * (N - 1) MB, and protects against a failure However this still will not allow s390 to build MD_RAID456. This dependency is in place because the xor.o object has moved from drivers/md to drivers/dma. The goal of the interface is to support using offload engines when they are present, and use software routines (like xor_block) when engines are not available. In other words, the intent is that DMA_ENGINE=n && ASYNC_TX_DMA=y is a valid configuration. Can we rework the !S390 change to the DMA_ENGINE menu? It seems to me that S390 should follow the ARM example and only enable the driver menus they want in arch/s390/Kconfig, no? ... On a closer look, it seems async_tx should be its own directory like crypto... I'll post the incremental changes to the md-accel git tree for review. Dan - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/