On 10/14/24 4:54 PM, Ritesh Harjani (IBM) wrote: > Madhavan Srinivasan <maddy@xxxxxxxxxxxxx> writes: > >> On 10/11/24 8:30 PM, Ritesh Harjani (IBM) wrote: >>> We anyway don't use any return values from fadump_cma_init(). Since >>> fadump_reserve_mem() from where fadump_cma_init() gets called today, >>> already has the required checks. >>> This patch makes this function return type as void. Let's also handle >>> extra cases like return if fadump_supported is false or dump_active, so >>> that in later patches we can call fadump_cma_init() separately from >>> setup_arch(). >> >> Usually patches to this file are posted with title format of >> >> powerpc/fadump:<> > > yes. I guess it is good to do it that way (I might have missed it) > Although commit history of oldest few patches to fadump shows.. > > ebaeb5ae2437 fadump: Convert firmware-assisted cpu state dump data into elf notes. > 2df173d9e85d fadump: Initialize elfcore header and add PT_LOAD program headers. > 3ccc00a7e04f fadump: Register for firmware assisted dump. > eb39c8803d0e fadump: Reserve the memory for firmware assisted dump. > >> >> >>> >>> Acked-by: Hari Bathini <hbathini@xxxxxxxxxxxxx> >>> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@xxxxxxxxx> >>> --- >>> v2 -> v3: Separated the series into 2 as discussed in v2. >>> [v2]: https://lore.kernel.org/linuxppc-dev/cover.1728585512.git.ritesh.list@xxxxxxxxx/ >>> >>> arch/powerpc/kernel/fadump.c | 23 +++++++++-------------- >>> 1 file changed, 9 insertions(+), 14 deletions(-) >>> >>> diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c >>> index a612e7513a4f..162327d66982 100644 >>> --- a/arch/powerpc/kernel/fadump.c >>> +++ b/arch/powerpc/kernel/fadump.c >>> @@ -78,27 +78,23 @@ static struct cma *fadump_cma; >>> * But for some reason even if it fails we still have the memory reservation >>> * with us and we can still continue doing fadump. >>> */ >>> -static int __init fadump_cma_init(void) >>> +static void __init fadump_cma_init(void) >>> { >>> unsigned long long base, size; >>> int rc; >>> >>> - if (!fw_dump.fadump_enabled) >>> - return 0; >>> - >>> + if (!fw_dump.fadump_supported || !fw_dump.fadump_enabled || >>> + fw_dump.dump_active) >>> + return; >> >> Is these checks even needed here? fadump_reserve_mem() checked for all >> these already, also dont see any other caller for fadump_cma_init(). >> >> > > In the next patch we will move fadump_cma_init() call from within > fadump_reserve_mem() to setup_arch(). Hence we need these extra checks > in fadump_cma_init() as well. I mentioned the same in the commit msg of > this patch too. > yes, just saw that when looking at the patch 3, sorry for the noise. >>> /* >>> * Do not use CMA if user has provided fadump=nocma kernel parameter. >>> - * Return 1 to continue with fadump old behaviour. >>> */ >>> - if (fw_dump.nocma) >>> - return 1; >>> + if (fw_dump.nocma || !fw_dump.boot_memory_size) >>> + return; >>> >>> base = fw_dump.reserve_dump_area_start; >>> size = fw_dump.boot_memory_size; >>> >>> - if (!size) >>> - return 0; >> >> So this is the only place where we return 0, which in turn will make the >> "ret" in fadump_reserve_mem() as zero forcing to call reserve_crashkernel() >> in early_init_devtree(). >> >> we are removing it, becos we know "size" here will never be zero? >> >> > > yes. Because we already check if boot_memory_size is less than > bootmem_min in fadump_reserve_mem(). If it is less, then we fail and > disable fadump (fadump_enabled = 0). > Thanks for the clarification. > So then there is no need to check for !boot_memory_size in here. > > fadump_reseve_mem( ) { > <...> > if (!fw_dump.dump_active) { > fw_dump.boot_memory_size = > PAGE_ALIGN(fadump_calculate_reserve_size()); > > bootmem_min = fw_dump.ops->fadump_get_bootmem_min(); > if (fw_dump.boot_memory_size < bootmem_min) { > pr_err("Can't enable fadump with boot memory size (0x%lx) less than 0x%llx\n", > fw_dump.boot_memory_size, bootmem_min); > goto error_out; > } > <...> > } > <...> > error_out: > fw_dump.fadump_enabled = 0; > fw_dump.reserve_dump_area_size = 0; > return 0; > } > > > Thanks for the review! > -ritesh