Commit ad6c00283163 ("swiotlb: Free tbl memory in swiotlb_exit()")
introduced a set_memory_encrypted() call to swiotlb_exit() so that the
buffer pages are returned to an encrypted state prior to being freed.Sachin reports that this leads to the following crash on a Power server: [ 0.010799] software IO TLB: tearing down default memory pool [ 0.010805] ------------[ cut here ]------------ [ 0.010808] kernel BUG at arch/powerpc/kernel/interrupt.c:98! Nick spotted that this is because set_memory_encrypted() is issuing an ultracall which doesn't exist for the processor, and should therefore be gated by mem_encrypt_active() to mirror the x86 implementation. Cc: Konrad Rzeszutek Wilk <[email protected]> Cc: Claire Chang <[email protected]> Cc: Christoph Hellwig <[email protected]> Cc: Robin Murphy <[email protected]> Fixes: ad6c00283163 ("swiotlb: Free tbl memory in swiotlb_exit()") Suggested-by: Nicholas Piggin <[email protected]> Reported-by: Sachin Sant <[email protected]> Tested-by: Sachin Sant <[email protected]> Tested-by: Nathan Chancellor <[email protected]> Link: https://lore.kernel.org/r/[email protected]/ Signed-off-by: Will Deacon <[email protected]> --- arch/powerpc/platforms/pseries/svm.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/powerpc/platforms/pseries/svm.c b/arch/powerpc/platforms/pseries/svm.c index 1d829e257996..87f001b4c4e4 100644 --- a/arch/powerpc/platforms/pseries/svm.c +++ b/arch/powerpc/platforms/pseries/svm.c @@ -63,6 +63,9 @@ void __init svm_swiotlb_init(void) int set_memory_encrypted(unsigned long addr, int numpages) { + if (!mem_encrypt_active()) + return 0; + if (!PAGE_ALIGNED(addr)) return -EINVAL; @@ -73,6 +76,9 @@ int set_memory_encrypted(unsigned long addr, int numpages) int set_memory_decrypted(unsigned long addr, int numpages) { + if (!mem_encrypt_active()) + return 0; + if (!PAGE_ALIGNED(addr)) return -EINVAL; -- 2.32.0.554.ge1b32706d8-goog _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
