Re: [PATCH v2 3/5] elf2dmp: introduce merging of physical memory runs

[Peter Maydell]

On Fri, 15 Sept 2023 at 18:02, Viktor Prutyanov <viktor@daynix.com> wrote:
>
> DMP supports 42 physical memory runs at most. So, merge adjacent
> physical memory ranges from QEMU ELF when possible to minimize total
> number of runs.
>
> Signed-off-by: Viktor Prutyanov <viktor@daynix.com>
> ---
>  contrib/elf2dmp/main.c | 56 ++++++++++++++++++++++++++++++++++++------
>  1 file changed, 48 insertions(+), 8 deletions(-)
>
> diff --git a/contrib/elf2dmp/main.c b/contrib/elf2dmp/main.c
> index b7e3930164..b4683575fd 100644
> --- a/contrib/elf2dmp/main.c
> +++ b/contrib/elf2dmp/main.c
> @@ -20,6 +20,7 @@
>  #define PE_NAME     "ntoskrnl.exe"
>
>  #define INITIAL_MXCSR   0x1f80
> +#define MAX_NUMBER_OF_RUNS  42
>
>  typedef struct idt_desc {
>      uint16_t offset1;   /* offset bits 0..15 */
> @@ -234,6 +235,42 @@ static int fix_dtb(struct va_space *vs, QEMU_Elf *qe)
>      return 1;
>  }
>
> +static void try_merge_runs(struct pa_space *ps,
> +        WinDumpPhyMemDesc64 *PhysicalMemoryBlock)
> +{
> +    unsigned int merge_cnt = 0, run_idx = 0;
> +
> +    PhysicalMemoryBlock->NumberOfRuns = 0;
> +
> +    for (size_t idx = 0; idx < ps->block_nr; idx++) {
> +        struct pa_block *blk = ps->block + idx;
> +        struct pa_block *next = blk + 1;
> +
> +        PhysicalMemoryBlock->NumberOfPages += blk->size / ELF2DMP_PAGE_SIZE;
> +
> +        if (idx + 1 != ps->block_nr && blk->paddr + blk->size == 
> next->paddr) {
> +            printf("Block #%lu 0x%"PRIx64"+:0x%"PRIx64" and %u previous will 
> be"
> +                    " merged\n", idx, blk->paddr, blk->size, merge_cnt);
> +            merge_cnt++;
> +        } else {
> +            struct pa_block *first_merged = blk - merge_cnt;
> +
> +            printf("Block #%lu 0x%"PRIx64"+:0x%"PRIx64" and %u previous will 
> be"
> +                    " merged to 0x%"PRIx64"+:0x%"PRIx64" (run #%u)\n",
> +                    idx, blk->paddr, blk->size, merge_cnt, 
> first_merged->paddr,
> +                    blk->paddr + blk->size - first_merged->paddr, run_idx);
> +            PhysicalMemoryBlock->Run[run_idx] = (WinDumpPhyMemRun64) {
> +                .BasePage = first_merged->paddr / ELF2DMP_PAGE_SIZE,
> +                .PageCount = (blk->paddr + blk->size - first_merged->paddr) /
> +                        ELF2DMP_PAGE_SIZE,
> +            };

Hi; this fails to build on 32-bit hosts because in both these printf()
statements the format string uses "%lu" to print a size_t. This
doesn't work if size_t is not a 'long'. The right format operator is "%zu".

I have squashed in the relevant change to this patch in target-arm.next.

thanks
-- PMM