kernel.git/arch/powerpc/platforms/cell, branch linux-2.6.28.y

powerpc/cell/axon-msi: Fix MSI after kexec

2008-12-16T02:48:18Z

Commit d015fe995 'powerpc/cell/axon-msi: Retry on missing interrupt' has turned a rare failure to kexec on QS22 into a reproducible error, which we have now analysed. The problem is that after a kexec, the MSIC hardware still points into the middle of the old ring buffer. We set up the ring buffer during reboot, but not the offset into it. On older kernels, this would cause a storm of thousands of spurious interrupts after a kexec, which would most of the time get dropped silently. With the new code, we time out on each interrupt, waiting for it to become valid. If more interrupts come in that we time out on, this goes on indefinitely, which eventually leads to a hard crash. The solution in this commit is to read the current offset from the MSIC when reinitializing it. This now works correctly, as expected. Reported-by: Dirk Herrendoerfer Signed-off-by: Arnd Bergmann Acked-by: Michael Ellerman Signed-off-by: Paul Mackerras

powerpc/cell: Fix GDB watchpoints, again

2008-11-30T22:40:18Z

An earlier patch from Jens Osterkamp attempted to fix GDB watchpoints by enabling the DABRX register at boot time. Unfortunately, this did not work on SMP setups, where secondary CPUs were still using the power-on DABRX value. This introduces the same change for secondary CPUs on cell as well. Reported-by: Ulrich Weigand Tested-by: Ulrich Weigand Signed-off-by: Arnd Bergmann Signed-off-by: Paul Mackerras

powerpc/cell/axon-msi: Retry on missing interrupt

2008-11-30T22:40:18Z

The MSI capture logic for the axon bridge can sometimes lose interrupts in case of high DMA and interrupt load, when it signals an MSI interrupt to the MPIC interrupt controller while we are already handling another MSI. Each MSI vector gets written into a FIFO buffer in main memory using DMA, and that DMA access is normally flushed by the actual interrupt packet on the IOIF. An MMIO register in the MSIC holds the position of the last entry in the FIFO buffer that was written. However, reading that position does not flush the DMA, so that we can observe stale data in the buffer. In a stress test, we have observed the DMA to arrive up to 14 microseconds after reading the register. This patch works around this problem by retrying the access to the FIFO buffer. We can reliably detect the conditioning by writing an invalid MSI vector into the FIFO buffer after reading from it, assuming that all MSIs we get are valid. After detecting an invalid MSI vector, we udelay(1) in the interrupt cascade for up to 100 times before giving up. Signed-off-by: Arnd Bergmann Signed-off-by: Paul Mackerras

Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/jk/spufs into merge

2008-11-24T00:54:08Z

powerpc/spufs: Fix spinning in spufs_ps_fault on signal

2008-11-20T23:14:16Z

Currently, we can end up in an infinite loop if we get a signal while the kernel has faulted in spufs_ps_fault. Eg: alarm(1); write(fd, some_spu_psmap_register_address, 4); - the write's copy_from_user will fault on the ps mapping, and signal_pending will be non-zero. Because returning from the fault handler will never clear TIF_SIGPENDING, so we'll just keep faulting, resulting in an unkillable process using 100% of CPU. This change returns VM_FAULT_SIGBUS if there's a fatal signal pending, letting us escape the loop. Signed-off-by: Jeremy Kerr

powerpc/cell: Fix compile error in ras.c

2008-11-05T08:59:08Z

This fixes this error on Cell when CONFIG_KEXEC = n: arch/powerpc/platforms/cell/ras.c:299: error: implicit declaration of function 'crash_shutdown_register' We have to include because it contains the dummy definition of crash_shutdown_register that is used when CONFIG_KEXEC=n, but doesn't include in that case. Signed-off-by: Alexey Dobriyan Signed-off-by: Paul Mackerras

powerpc: Update remaining dma_mapping_ops to use map/unmap_page

2008-10-31T05:13:48Z

After the merge of the 32 and 64bit DMA code, dma_direct_ops lost their map/unmap_single() functions but gained map/unmap_page(). This caused a problem for Cell because Cell's dma_iommu_fixed_ops called the dma_direct_ops if the fixed linear mapping was to be used or the iommu ops if the dynamic window was to be used. So in order to fix this problem we need to update the 64bit DMA code to use map/unmap_page. First, we update the generic IOMMU code so that iommu_map_single() becomes iommu_map_page() and iommu_unmap_single() becomes iommu_unmap_page(). Then we propagate these changes up through all the callers of these two functions and in the process update all the dma_mapping_ops so that they have map/unmap_page rahter than map/unmap_single. We can do this because on 64bit there is no HIGHMEM memory so map/unmap_page ends up performing exactly the same function as map/unmap_single, just taking different arguments. This has no affect on drivers because the dma_map_single_attrs() just ends up calling the map_page() function of the appropriate dma_mapping_ops and similarly the dma_unmap_single_attrs() calls unmap_page(). This fixes an oops on Cell blades, which oops on boot without this because they call dma_direct_ops.map_single, which is NULL. Signed-off-by: Mark Nelson Signed-off-by: Paul Mackerras

powerpc: Use is_kdump_kernel()

2008-10-31T05:11:47Z

linux/crash_dump.h defines is_kdump_kernel() to be used by code that needs to know if the previous kernel crashed instead of a (clean) boot or reboot. This updates the just added powerpc code to use it. This is needed for the next commit, which will remove __kdump_flag. Signed-off-by: Milton Miller Signed-off-by: Paul Mackerras

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6

2008-10-23T17:22:40Z

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (46 commits) [PATCH] fs: add a sanity check in d_free [PATCH] i_version: remount support [patch] vfs: make security_inode_setattr() calling consistent [patch 1/3] FS_MBCACHE: don't needlessly make it built-in [PATCH] move executable checking into ->permission() [PATCH] fs/dcache.c: update comment of d_validate() [RFC PATCH] touch_mnt_namespace when the mount flags change [PATCH] reiserfs: add missing llseek method [PATCH] fix ->llseek for more directories [PATCH vfs-2.6 6/6] vfs: add LOOKUP_RENAME_TARGET intent [PATCH vfs-2.6 5/6] vfs: remove LOOKUP_PARENT from non LOOKUP_PARENT lookup [PATCH vfs-2.6 4/6] vfs: remove unnecessary fsnotify_d_instantiate() [PATCH vfs-2.6 3/6] vfs: add __d_instantiate() helper [PATCH vfs-2.6 2/6] vfs: add d_ancestor() [PATCH vfs-2.6 1/6] vfs: replace parent == dentry->d_parent by IS_ROOT() [PATCH] get rid of on-stack dentry in udf [PATCH 2/2] anondev: switch to IDA [PATCH 1/2] anondev: init IDR statically [JFFS2] Use d_splice_alias() not d_add() in jffs2_lookup() [PATCH] Optimise NFS readdir hack slightly. ...

[PATCH] don't pass bogus flags to LOOKUP_PARENT lookup in spufs

2008-10-23T09:12:55Z

Signed-off-by: Al Viro