Re: [Qemu-devel] [PATCH] pflash: flush rom device memory region

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

On 1/25/19 4:57 PM, Stefan Hajnoczi wrote:
> pflash devices should mark the memory region dirty and invalidate TBs
> after directly writing to the RAM backing the ROM device.
> 
> Note that pflash_cfi01_get_memory() is used by several machine types to
> populate ROM contents directly.  Callers are untouched by this patch
> because they only modify memory before the guest is started.
> 
> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>

> ---
> Based-on: <20190123212234.32068-1-stefanha@redhat.com>
> 
> Split from the original patch series.  Philippe asked me to drop the
> flush calls in ->realize() since they are unnecessary.
> 
> Peter: Your ARM tree has the memory_region_flush_rom_device() patch that
> this depends on, so it may be easiest for this to go via your tree.
> 
>  hw/block/pflash_cfi01.c | 3 +++
>  hw/block/pflash_cfi02.c | 6 ++++++
>  2 files changed, 9 insertions(+)
> 
> diff --git a/hw/block/pflash_cfi01.c b/hw/block/pflash_cfi01.c
> index bffb4c40e7..2f0b9c4c02 100644
> --- a/hw/block/pflash_cfi01.c
> +++ b/hw/block/pflash_cfi01.c
> @@ -446,6 +446,7 @@ static inline void pflash_data_write(pflash_t *pfl, hwaddr offset,
>          break;
>      }
>  
> +    memory_region_flush_rom_device(&pfl->mem, offset, width);
>  }
>  
>  static void pflash_write(pflash_t *pfl, hwaddr offset,
> @@ -482,6 +483,8 @@ static void pflash_write(pflash_t *pfl, hwaddr offset,
>              if (!pfl->ro) {
>                  memset(p + offset, 0xff, pfl->sector_len);
>                  pflash_update(pfl, offset, pfl->sector_len);
> +                memory_region_flush_rom_device(&pfl->mem, offset,
> +                                               pfl->sector_len);
>              } else {
>                  pfl->status |= 0x20; /* Block erase error */
>              }
> diff --git a/hw/block/pflash_cfi02.c b/hw/block/pflash_cfi02.c
> index 0f8b7b8c7b..47edce8dcf 100644
> --- a/hw/block/pflash_cfi02.c
> +++ b/hw/block/pflash_cfi02.c
> @@ -378,6 +378,8 @@ static void pflash_write (pflash_t *pfl, hwaddr offset,
>                      pflash_update(pfl, offset, 4);
>                      break;
>                  }
> +
> +                memory_region_flush_rom_device(&pfl->orig_mem, offset, width);
>              }
>              pfl->status = 0x00 | ~(value & 0x80);
>              /* Let's pretend write is immediate */
> @@ -426,6 +428,8 @@ static void pflash_write (pflash_t *pfl, hwaddr offset,
>              if (!pfl->ro) {
>                  memset(pfl->storage, 0xFF, pfl->chip_len);
>                  pflash_update(pfl, 0, pfl->chip_len);
> +                memory_region_flush_rom_device(&pfl->orig_mem, 0,
> +                                               pfl->chip_len);
>              }
>              pfl->status = 0x00;
>              /* Let's wait 5 seconds before chip erase is done */
> @@ -441,6 +445,8 @@ static void pflash_write (pflash_t *pfl, hwaddr offset,
>              if (!pfl->ro) {
>                  memset(p + offset, 0xFF, pfl->sector_len);
>                  pflash_update(pfl, offset, pfl->sector_len);
> +                memory_region_flush_rom_device(&pfl->orig_mem, offset,
> +                                               pfl->sector_len);
>              }
>              pfl->status = 0x00;
>              /* Let's wait 1/2 second before sector erase is done */
>