Re: [PATCH] riscv: Drop setup_initrd

From: Palmer Dabbelt
Date: Tue Aug 28 2018 - 16:10:24 EST


On Thu, 09 Aug 2018 21:11:40 PDT (-0700), linux@xxxxxxxxxxxx wrote:
setup_initrd() does not appear to serve a practical purpose other than
preventing qemu boots with "-initrd" parameter, so let's drop it.

Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
---
arch/riscv/kernel/setup.c | 39 ---------------------------------------
1 file changed, 39 deletions(-)

diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index 2e56af3281f8..579f58a42974 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -82,41 +82,6 @@ EXPORT_SYMBOL(empty_zero_page);
/* The lucky hart to first increment this variable will boot the other cores */
atomic_t hart_lottery;

-#ifdef CONFIG_BLK_DEV_INITRD
-static void __init setup_initrd(void)
-{
- extern char __initramfs_start[];
- extern unsigned long __initramfs_size;
- unsigned long size;
-
- if (__initramfs_size > 0) {
- initrd_start = (unsigned long)(&__initramfs_start);
- initrd_end = initrd_start + __initramfs_size;
- }
-
- if (initrd_start >= initrd_end) {
- printk(KERN_INFO "initrd not found or empty");
- goto disable;
- }
- if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
- printk(KERN_ERR "initrd extends beyond end of memory");
- goto disable;
- }
-
- size = initrd_end - initrd_start;
- memblock_reserve(__pa(initrd_start), size);
- initrd_below_start_ok = 1;
-
- printk(KERN_INFO "Initial ramdisk at: 0x%p (%lu bytes)\n",
- (void *)(initrd_start), size);
- return;
-disable:
- pr_cont(" - disabling initrd\n");
- initrd_start = 0;
- initrd_end = 0;
-}
-#endif /* CONFIG_BLK_DEV_INITRD */
-
pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
pgd_t trampoline_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);

@@ -195,10 +160,6 @@ static void __init setup_bootmem(void)
set_max_mapnr(PFN_DOWN(mem_size));
max_low_pfn = pfn_base + PFN_DOWN(mem_size);

-#ifdef CONFIG_BLK_DEV_INITRD
- setup_initrd();
-#endif /* CONFIG_BLK_DEV_INITRD */
-
early_init_fdt_reserve_self();
early_init_fdt_scan_reserved_mem();
memblock_allow_resize();

With this patch I can't boot in QEMU. It might be something with my setup, though. I'm testing with a unified BBL+vmlinux, and using QEMU 3.0.0-rc3 (I should probably update that one, but I don't remember anything going by). Do you have time to take a look? Here's my QEMU commandline

./riscv64-softmmu/qemu-system-riscv64 -nographic -machine virt -smp 4 -m 2G -kernel /home/palmer/work/riscv/riscv-pk/build/bbl -object rng-random,filename=/dev/urandom,id=rng0 -device virtio-rng-device,rng=rng0 -append "console=ttyS0 ro root=/dev/vda" -device virtio-blk-device,drive=hd0 -drive file=stage4-disk.img,format=raw,id=hd0 -device virtio-net-device,netdev=usernet -netdev user,id=usernet,hostfwd=tcp::10000-:22

I just tagged the PR I plan to submit for RC2 tomorrow, so at least it should be easy for everyone to get on the same page.