On Fri, Jun 5, 2026 at 1:57 AM <[email protected]> wrote: > > From: Pravin M Bathija <[email protected]> > > This is version v15 of the patchset and it incorporates the > recommendations made by Maxime Coquelin. > > Patch 4/5 > - Changed VHOST_USER_REM_MEM_REG handler declaration from > accepts_fd=true to accepts_fd=false, as the remove request does not > expect FDs in ancillary data. > - Removed all close_msg_fds(ctx) calls from vhost_user_rem_mem_reg(), no > longer needed since the handler is declared as not accepting FDs. > - Removed validate_msg_fds(dev, ctx, 0) check from > vhost_user_rem_mem_reg(), as FD validation is now handled generically > by the framework. > - Added targeted IOTLB cache invalidation in vhost_user_rem_mem_reg() > using vhost_user_iotlb_cache_remove() for the removed region's GPA > range, instead of the nuclear iotlb_flush_all() used by set_mem_table. > > This implementation has been extensively tested by doing Read/Write I/O > from multiple instances of fio + libblkio (front-end) talking to > spdk/dpdk (back-end) based drives. Tested with qemu front-end talking to > dpdk testpmd (back-end) performing add/removal of memory regions. Also > tested post-copy live migration after doing add_memory_region. > > Version Log: > Version v15 (Current version): Incorporate code review suggestions from > Maxime Coquelin as described above. > > Version v14: Incorporate code review suggestions from Stephen Hemminger > and Fengcheng Wen. > Changes from Fengcheng Wen review: > Patch 3/5 > - Moved free_all_mem_regions() call sites in vhost_user_set_mem_table() > from patch 4/5 to patch 3/5 so each commit compiles independently > Patch 4/5 > - Renamed _dev_invalidate_vrings() to vhost_user_invalidate_vrings() to > follow vhost naming convention > - Added comment explaining *pdev propagation through > translate_ring_addresses / numa_realloc() > - Reordered local variables in vhost_user_add_mem_reg() and > vhost_user_rem_mem_reg() by descending line length > - Shortened overlap check variable names (current_region_guest_start/end > --> cur_start/end, proposed_region_guest_start/end -> new_start/end) > - Fixed DMA error path in vhost_user_add_mem_reg(): added > free_new_region_no_dma label so async_dma_map_region(false) is not > called when the map itself failed. > Changes from Stephen Hemminger review: > Patch 4/5 > - vhost_user_add_mem_reg() now constructs a reply with the back-end's > host mapping address in userspace_addr and returns > RTE_VHOST_MSG_RESULT_REPLY per the vhost-user spec > - Added validate_msg_fds(dev, ctx, 0) in vhost_user_rem_mem_reg() to > reject malformed messages with unexpected file descriptors > - Dropped unnecessary (uint64_t) cast in vhost_user_get_max_mem_slots() > > Version v13: Incorporate code review suggestions from Fengcheng Wen > Patch 2/5 > Renamed VhostUserSingleMemReg to VhostUserMemRegMsg and memory_single > to memreg > Patches 3/5 and 4/5 > Relocated function remove_guest_pages from patch 3/5 to 4/5 > > Version v12: Incorporate code review suggestions from Maxime Coquelin > and ai-code-review. > Patch 3/5 > Refactored async_dma_map() to delegate to async_dma_map_region(), > eliminating code duplication between the two functions. > Restored original comments in async_dma_map_region() explaining why > ENODEV and EINVAL errors are ignored (these were stripped in v10) > Reverted unnecessary changes to vhost_user_postcopy_register() -- > removed the host_user_addr == 0 checks and reg_msg_index indirection > that were added in v10, since this function is only called from > vhost_user_set_mem_table() where regions are always contiguous. > > Version v11: Incorporate code review suggestions from Stephen Hemminger. > Patch 4/5 > Fix incomplete cleanup in vhost_user_add_mem_reg() when > vhost_user_mmap_region() fails after the mmap succeeds (e.g. > add_guest_pages() realloc failure) realloc failure). The error path now > calls remove_guest_pages() and free_mem_region() to undo the mapping > and stale guest-page entries, preventing a leaked mmap and slot reuse > corruption. The plain close(fd) path is kept for pre-mmap failures. > > Version v10: Incorporate code review suggestions from Stephen Hemminger. > Patch 4/5 > Moved dev_invalidate_vrings after free_mem_region, array compaction, and > nregions decrement. This ensures translate_ring_addresses only sees > surviving memory regions, preventing vring pointers from resolving into > a region that is about to be unmapped. > > Version v9: Incorporate code review suggestions from Stephen Hemminger. > Patch 3/5 > Restored max_guest_pages initial value to hardcoded 8 instead of > VHOST_MEMORY_MAX_NREGIONS, matching upstream semantics. > Patch 4/5 > Added close(reg->fd) and reg->fd = -1 before goto close_msg_fds in the > mmap failure path to fix fd leak after fd was moved from ctx->fds[0]. > Converted dev_invalidate_vrings from a plain function to a macro + > implementation function pair, accepting message ID as a parameter so > the static_assert reports the correct handler at each call site. > Updated dev_invalidate_vrings call in add_mem_reg to pass > VHOST_USER_ADD_MEM_REG as message ID. > Updated dev_invalidate_vrings call in rem_mem_reg to pass > VHOST_USER_REM_MEM_REG as message ID. > > Version v8: Incorporate code review suggestions from Stephen Hemminger. > rewrite async_dma_map_region function to iterate guest pages by host > address range matching > change function dev_invalidate_vrings to accept a double pointer to > propagate pointer updates > new function remove_guest_pages was added > add_mem_reg error path was narrowed to only clean up the single failed > region instead of destroting all existing regions > > Version v7: Incorporate code review suggestions from Maxime Coquelin. > Add debug messages to vhost_postcopy_register function. > > Version v6: Added the enablement of this feature as a final patch in > this patch-set and other code optimizations as suggested by Maxime > Coquelin. > > Version v5: removed the patch that increased the number of memory regions > from 8 to 128. This will be submitted as a separate feature at a later > point after incorporating additional optimizations. Also includes code > optimizations as suggested by Feng Cheng Wen. > > Version v4: code optimizations as suggested by Feng Cheng Wen. > > Version v3: code optimizations as suggested by Maxime Coquelin > and Thomas Monjalon. > > Version v2: code optimizations as suggested by Maxime Coquelin. > > Version v1: Initial patch set. > > Pravin M Bathija (5): > vhost: add user to mailmap and define to vhost hdr > vhost: header defines for add/rem mem region > vhost: refactor memory helper functions > vhost: add mem region add/remove handlers > vhost: enable configure memory slots > > .mailmap | 1 + > lib/vhost/rte_vhost.h | 4 + > lib/vhost/vhost_user.c | 425 +++++++++++++++++++++++++++++++++++------ > lib/vhost/vhost_user.h | 10 + > 4 files changed, 378 insertions(+), 62 deletions(-) > > -- > 2.43.0 >
Applied to next-virtio/for-next-net. Thanks, Maxime
