Patrick Rudolph has submitted this change and it was merged. ( https://review.coreboot.org/c/coreboot/+/33426 )
Change subject: mb/emulation/qemu-riscv: Protect CBFS from payload loader ......................................................................
mb/emulation/qemu-riscv: Protect CBFS from payload loader
The virt machine is special as it doesn't emulate flash and it puts the coreboot.rom at start of DRAM. The payload loader doesn't know about CBFS in DRAM and overwrites the CBFS while decompressing payloads, resulting in undefined behaviour.
Mark the region as SRAM to make sure the payload won't overwrite the CBFS while decompressing. As payload is always decompressed to DRAM, it wouldn't touch SRAM memory regions.
Change-Id: I36a18cb727f660ac9e77df413026627ea160c1e1 Signed-off-by: Patrick Rudolph patrick.rudolph@9elements.com Reviewed-on: https://review.coreboot.org/c/coreboot/+/33426 Tested-by: build bot (Jenkins) no-reply@coreboot.org Reviewed-by: Philipp Deppenwiese zaolin.daisuki@gmail.com --- M src/mainboard/emulation/qemu-riscv/memlayout.ld M src/mainboard/emulation/qemu-riscv/rom_media.c 2 files changed, 13 insertions(+), 6 deletions(-)
Approvals: build bot (Jenkins): Verified Philipp Deppenwiese: Looks good to me, approved
diff --git a/src/mainboard/emulation/qemu-riscv/memlayout.ld b/src/mainboard/emulation/qemu-riscv/memlayout.ld index 7f8ec3d..2166d23 100644 --- a/src/mainboard/emulation/qemu-riscv/memlayout.ld +++ b/src/mainboard/emulation/qemu-riscv/memlayout.ld @@ -17,16 +17,23 @@ #include <arch/header.ld> #include <mainboard/addressmap.h>
-//Stages start after CBFS in DRAM +// Stages start after CBFS in DRAM #define STAGES_START (QEMU_VIRT_DRAM + CONFIG_ROM_SIZE)
SECTIONS { - DRAM_START(QEMU_VIRT_DRAM) + // the virt target doesn't emulate flash and just puts the CBFS into DRAM. + // fake SRAM where CBFS resides. It's only done for better integration. + SRAM_START(QEMU_VIRT_DRAM) BOOTBLOCK(QEMU_VIRT_DRAM, 64K) // CBFS goes here - STACK(STAGES_START, 4K) - ROMSTAGE(STAGES_START + 64K, 128K) - PRERAM_CBMEM_CONSOLE(STAGES_START + 192K, 8K) + SRAM_END(STAGES_START) + DRAM_START(STAGES_START) + +#if ENV_ROMSTAGE + ROMSTAGE(STAGES_START, 128K) +#endif + PRERAM_CBMEM_CONSOLE(STAGES_START + 128K, 8K) RAMSTAGE(STAGES_START + 200K, 16M) + STACK(STAGES_START + 200K + 16M, 4K) } diff --git a/src/mainboard/emulation/qemu-riscv/rom_media.c b/src/mainboard/emulation/qemu-riscv/rom_media.c index bac1984..79e5ca8 100644 --- a/src/mainboard/emulation/qemu-riscv/rom_media.c +++ b/src/mainboard/emulation/qemu-riscv/rom_media.c @@ -19,7 +19,7 @@ /* This assumes that the CBFS resides at start of dram, which is true for the * default configuration. */ static const struct mem_region_device boot_dev = - MEM_REGION_DEV_RO_INIT(_dram, CONFIG_ROM_SIZE); + MEM_REGION_DEV_RO_INIT(_sram, CONFIG_ROM_SIZE);
const struct region_device *boot_device_ro(void) {