Re: [PATCH v15 00/11] fw_cfg: add DMA operations & etc/vmcoreinfo support

[Michael S. Tsirkin]

On Thu, Feb 15, 2018 at 10:33:01PM +0100, Marc-André Lureau wrote:
> Hi,
> 
> This series adds DMA operations support to the qemu fw_cfg kernel
> module and populates "etc/vmcoreinfo" with vmcoreinfo location
> details (entry added since qemu 2.11 with -device vmcoreinfo).

Pls reorder with patches 3-7 first as these are fixes.

> v15:
> - fix fw_cfg.h uapi header #include
> - use BSD license for fw_cfg.h uapi header
> - move the uapi defines/structs for DMA & vmcoreinfo in the
>   corresponding patch
> - use cpu_relax() instead of usleep_range(50, 100);
> - replace do { } while(true) by for (;;)
> - fix the rmb() call location
> - add a preliminary patch to handle error from fw_cfg_write_blob()
> - rewrite fw_cfg_sel_endianness() to wrap iowrite() calls
> 
> v14:
> - add "fw_cfg: add a public uapi header"
> - fix sparse warnings & don't introduce new warnings
> - add memory barriers to force IO ordering
> - split fw_cfg_read_blob() in fw_cfg_read_blob_io() and
>   fw_cfg_read_blob_dma()
> - add error handling to fw_cfg_read_blob() callers
> - minor stylistic changes
> 
> v13:
> - reorder patch series, introduce DMA write before DMA read
> - do some measurements of DMA read speed-ups
> 
> v12:
> - fix virt_to_phys(NULL) panic with CONFIG_DEBUG_VIRTUAL=y
> - do not use DMA read, except for kmalloc() memory we allocated
>   ourself (only fw_cfg_register_dir_entries() so far)
> 
> v11:
> - add #include <linux/crash_core.h> in last patch,
>   fixing kbuild .config test
> 
> Marc-André Lureau (11):
>   crash: export paddr_vmcoreinfo_note()
>   fw_cfg: add a public uapi header
>   fw_cfg: fix sparse warnings in fw_cfg_sel_endianness()
>   fw_cfg: fix sparse warnings with fw_cfg_file
>   fw_cfg: fix sparse warning reading FW_CFG_ID
>   fw_cfg: fix sparse warnings around FW_CFG_FILE_DIR read
>   fw_cfg: remove inline from fw_cfg_read_blob()
>   fw_cfg: handle fw_cfg_read_blob() error
>   fw_cfg: add DMA register
>   fw_cfg: write vmcoreinfo details
>   RFC: fw_cfg: do DMA read operation
> 
>  MAINTAINERS                    |   1 +
>  drivers/firmware/qemu_fw_cfg.c | 334 +++++++++++++++++++++++++++++++++--------
>  include/uapi/linux/fw_cfg.h    |  97 ++++++++++++
>  kernel/crash_core.c            |   1 +
>  4 files changed, 369 insertions(+), 64 deletions(-)
>  create mode 100644 include/uapi/linux/fw_cfg.h
> 
> -- 
> 2.16.1.73.g5832b7e9f2