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. >> /* >> * 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). 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
