Re: [PATCH v2] hw/riscv: virt: bugfix the memory-backend-file command is invalid
On Mon, 18 Oct 2021 10:17:45 +0800 Bin Meng wrote: > Hi Igor, > > On Fri, Oct 15, 2021 at 8:59 PM Igor Mammedov wrote: > > > > On Fri, 15 Oct 2021 17:25:01 +0800 > > Bin Meng wrote: > > > > > On Fri, Oct 15, 2021 at 4:52 PM limingwang (A) > > > wrote: > > > > > > > > > > > > On Wed, Oct 13, 2021 at 22:41 PM Bin Meng > > > > wrote: > > > > > > > > > > On Tue, Oct 12, 2021 at 9:46 AM MingWang Li > > > > > wrote: > > > > > > > > > > > > From: Mingwang Li > > > > > > > > > > > > When I start the VM with the following command: > > > > > > $ ./qemu-system-riscv64 -M virt,accel=kvm -m 4096M -cpu host > > > > > > -nographic \ > > > > > > -name guest=riscv-guset \ > > > > > > -smp 2 \ > > > > > > -bios none \ > > > > > > -kernel ./Image \ > > > > > > -drive file=./guest.img,format=raw,id=hd0 \ > > > > > > -device virtio-blk-device,drive=hd0 \ > > > > > > -append "root=/dev/vda rw console=ttyS0 earlycon=sbi" \ > > > > > > -object > > > > > memory-backend-file,id=mem,size=4096M,mem-path=/dev/hugepages,share=on > > > > > \ > > > > > > -numa node,memdev=mem -mem-prealloc \ > > > > > > -chardev socket,id=char0,path=/mnt/vhost-net0 \ > > > > > > -netdev type=vhost-user,id=mynet1,chardev=char0,vhostforce \ > > > > > > -device > > > > > > virtio-net-pci,mac=52:54:00:00:00:01,netdev=mynet1,mrg_rxbuf=on,csum=o > > > > > > n,guest_csum=on,guest_ecn=on \ > > > > > > > > > > > > Then, QEMU displays the following error information: > > > > > > qemu-system-riscv64: Failed initializing vhost-user memory map, > > > > > > consider using -object memory-backend-file share=on > > > > > > > > > > I see your command line parameters already contain "-object > > > > > memory-backend-file > > > > > share=on", so this error message is not accurate. > > > > > > > > QEMU uses this command to alloc fd in the > > > > "memory_region_init_ram_from_file" function > > > > and assigns the value of fd to mr->ram_block-fd. If the QEMU uses the > > > > default memory to > > > > initialize the system, the QEMU cannot obtain the fd in the > > > > "vhost_user_mem_section_filter" > > > > function when initializing the vhost-user. As a result, an error is > > > > reported in the "vhost_user_fill_set_mem_table_msg" > > > > function. > > > > > > > > Because of the above bug, even if "-object memory-backend-file > > > > share=on" is added to the command line, > > > > the QEMU still reports an error. > > > > > > Yes, what I meant is that QEMU should not report such inaccurate > > > messages because of some random codes elsewhere. > > > > > > With current message, it suggested user use "-object > > > memory-backend-file share=on" in the command line, but it is already > > > used. So this is a false alarm. The "bug" is somewhere else. > > > > bug is in using memory_region_init_ram(), > > which can't possibly handle vhost-user, and can't work as expected with > > '-numa node,memdev' options. > > Before main ram infrastructure was converted to memdev, > > one should have used memory_region_allocate_system_memory() for > > allocating main RAM, so numa usecase was broken from the start. > > Later it old API was dropped in favor of more flexible/generic > > MachineState::ram approach (see commits 68a86dc15ccd..f0530f14c7c35d). > > Thanks for the detailed pointers. > > I wonder if it is possible to make the error message to be clearer, so > instead of having > > "qemu-system-riscv64: Failed initializing vhost-user memory map, > consider using -object memory-backend-file share=on" > > can we do: > > "qemu-system-riscv64: Failed initializing vhost-user memory map, > considering using MachineState::ram instead of manually initializing > RAM memory region." > > which is more straightforward? It would only make sense in context of this thread and give a hint to a developer how to fix bug in machine code but won't give a clue to the end user what's wrong with configuration. Maybe following would be better: "Failed initializing vhost-user memory map, vhost requires shared system memory." "See 'System Emulation::Device Emulation::Emulated Devices::vhost-user back ends' chapter in QEMU manual." the chapter gives an example how to correctly configure vhost-user (albeit using old style) > > > > > > Modulo commit message, patch looks good to me and does what > > every machine should do. (I though that I've converted every > > existing to generalized MachineState::ram but it looks like > > riscv was missed). > > Indeed all riscv boards are doing the same thing. > > > > > So we can model commit message after bd457782b3b0a, > > and also add that the patch fixes broken -numa node,memdev case, > > which never properly worked. It also opens possibility to > > use vhost-user/virtiosf with main RAM if main RAM is > > provided explicitly via machine.memory-backend option > > with shared memory backend. > > > > Btw: is there other riscv machines that allocate RAM directly?
Re: [PATCH v2] hw/riscv: virt: bugfix the memory-backend-file command is invalid
Hi Igor, On Fri, Oct 15, 2021 at 8:59 PM Igor Mammedov wrote: > > On Fri, 15 Oct 2021 17:25:01 +0800 > Bin Meng wrote: > > > On Fri, Oct 15, 2021 at 4:52 PM limingwang (A) > > wrote: > > > > > > > > > On Wed, Oct 13, 2021 at 22:41 PM Bin Meng wrote: > > > > > > > > On Tue, Oct 12, 2021 at 9:46 AM MingWang Li > > > > wrote: > > > > > > > > > > From: Mingwang Li > > > > > > > > > > When I start the VM with the following command: > > > > > $ ./qemu-system-riscv64 -M virt,accel=kvm -m 4096M -cpu host > > > > > -nographic \ > > > > > -name guest=riscv-guset \ > > > > > -smp 2 \ > > > > > -bios none \ > > > > > -kernel ./Image \ > > > > > -drive file=./guest.img,format=raw,id=hd0 \ > > > > > -device virtio-blk-device,drive=hd0 \ > > > > > -append "root=/dev/vda rw console=ttyS0 earlycon=sbi" \ > > > > > -object > > > > memory-backend-file,id=mem,size=4096M,mem-path=/dev/hugepages,share=on \ > > > > > -numa node,memdev=mem -mem-prealloc \ > > > > > -chardev socket,id=char0,path=/mnt/vhost-net0 \ > > > > > -netdev type=vhost-user,id=mynet1,chardev=char0,vhostforce \ > > > > > -device > > > > > virtio-net-pci,mac=52:54:00:00:00:01,netdev=mynet1,mrg_rxbuf=on,csum=o > > > > > n,guest_csum=on,guest_ecn=on \ > > > > > > > > > > Then, QEMU displays the following error information: > > > > > qemu-system-riscv64: Failed initializing vhost-user memory map, > > > > > consider using -object memory-backend-file share=on > > > > > > > > I see your command line parameters already contain "-object > > > > memory-backend-file > > > > share=on", so this error message is not accurate. > > > > > > QEMU uses this command to alloc fd in the > > > "memory_region_init_ram_from_file" function > > > and assigns the value of fd to mr->ram_block-fd. If the QEMU uses the > > > default memory to > > > initialize the system, the QEMU cannot obtain the fd in the > > > "vhost_user_mem_section_filter" > > > function when initializing the vhost-user. As a result, an error is > > > reported in the "vhost_user_fill_set_mem_table_msg" > > > function. > > > > > > Because of the above bug, even if "-object memory-backend-file share=on" > > > is added to the command line, > > > the QEMU still reports an error. > > > > Yes, what I meant is that QEMU should not report such inaccurate > > messages because of some random codes elsewhere. > > > > With current message, it suggested user use "-object > > memory-backend-file share=on" in the command line, but it is already > > used. So this is a false alarm. The "bug" is somewhere else. > > bug is in using memory_region_init_ram(), > which can't possibly handle vhost-user, and can't work as expected with > '-numa node,memdev' options. > Before main ram infrastructure was converted to memdev, > one should have used memory_region_allocate_system_memory() for > allocating main RAM, so numa usecase was broken from the start. > Later it old API was dropped in favor of more flexible/generic > MachineState::ram approach (see commits 68a86dc15ccd..f0530f14c7c35d). Thanks for the detailed pointers. I wonder if it is possible to make the error message to be clearer, so instead of having "qemu-system-riscv64: Failed initializing vhost-user memory map, consider using -object memory-backend-file share=on" can we do: "qemu-system-riscv64: Failed initializing vhost-user memory map, considering using MachineState::ram instead of manually initializing RAM memory region." which is more straightforward? > > > Modulo commit message, patch looks good to me and does what > every machine should do. (I though that I've converted every > existing to generalized MachineState::ram but it looks like > riscv was missed). Indeed all riscv boards are doing the same thing. > > So we can model commit message after bd457782b3b0a, > and also add that the patch fixes broken -numa node,memdev case, > which never properly worked. It also opens possibility to > use vhost-user/virtiosf with main RAM if main RAM is > provided explicitly via machine.memory-backend option > with shared memory backend. > > Btw: is there other riscv machines that allocate RAM directly? > (if yes, those should be fixed as well, a patch per machine) > I will see if I can get some patches to fix other riscv machines. Regards, Bin
Re: [PATCH v2] hw/riscv: virt: bugfix the memory-backend-file command is invalid
On Fri, 15 Oct 2021 17:25:01 +0800 Bin Meng wrote: > On Fri, Oct 15, 2021 at 4:52 PM limingwang (A) wrote: > > > > > > On Wed, Oct 13, 2021 at 22:41 PM Bin Meng wrote: > > > > > > On Tue, Oct 12, 2021 at 9:46 AM MingWang Li > > > wrote: > > > > > > > > From: Mingwang Li > > > > > > > > When I start the VM with the following command: > > > > $ ./qemu-system-riscv64 -M virt,accel=kvm -m 4096M -cpu host -nographic > > > > \ > > > > -name guest=riscv-guset \ > > > > -smp 2 \ > > > > -bios none \ > > > > -kernel ./Image \ > > > > -drive file=./guest.img,format=raw,id=hd0 \ > > > > -device virtio-blk-device,drive=hd0 \ > > > > -append "root=/dev/vda rw console=ttyS0 earlycon=sbi" \ > > > > -object > > > memory-backend-file,id=mem,size=4096M,mem-path=/dev/hugepages,share=on \ > > > > -numa node,memdev=mem -mem-prealloc \ > > > > -chardev socket,id=char0,path=/mnt/vhost-net0 \ > > > > -netdev type=vhost-user,id=mynet1,chardev=char0,vhostforce \ > > > > -device > > > > virtio-net-pci,mac=52:54:00:00:00:01,netdev=mynet1,mrg_rxbuf=on,csum=o > > > > n,guest_csum=on,guest_ecn=on \ > > > > > > > > Then, QEMU displays the following error information: > > > > qemu-system-riscv64: Failed initializing vhost-user memory map, > > > > consider using -object memory-backend-file share=on > > > > > > I see your command line parameters already contain "-object > > > memory-backend-file > > > share=on", so this error message is not accurate. > > > > QEMU uses this command to alloc fd in the > > "memory_region_init_ram_from_file" function > > and assigns the value of fd to mr->ram_block-fd. If the QEMU uses the > > default memory to > > initialize the system, the QEMU cannot obtain the fd in the > > "vhost_user_mem_section_filter" > > function when initializing the vhost-user. As a result, an error is > > reported in the "vhost_user_fill_set_mem_table_msg" > > function. > > > > Because of the above bug, even if "-object memory-backend-file share=on" is > > added to the command line, > > the QEMU still reports an error. > > Yes, what I meant is that QEMU should not report such inaccurate > messages because of some random codes elsewhere. > > With current message, it suggested user use "-object > memory-backend-file share=on" in the command line, but it is already > used. So this is a false alarm. The "bug" is somewhere else. bug is in using memory_region_init_ram(), which can't possibly handle vhost-user, and can't work as expected with '-numa node,memdev' options. Before main ram infrastructure was converted to memdev, one should have used memory_region_allocate_system_memory() for allocating main RAM, so numa usecase was broken from the start. Later it old API was dropped in favor of more flexible/generic MachineState::ram approach (see commits 68a86dc15ccd..f0530f14c7c35d). Modulo commit message, patch looks good to me and does what every machine should do. (I though that I've converted every existing to generalized MachineState::ram but it looks like riscv was missed). So we can model commit message after bd457782b3b0a, and also add that the patch fixes broken -numa node,memdev case, which never properly worked. It also opens possibility to use vhost-user/virtiosf with main RAM if main RAM is provided explicitly via machine.memory-backend option with shared memory backend. Btw: is there other riscv machines that allocate RAM directly? (if yes, those should be fixed as well, a patch per machine) > > This patch can solve this bug. > > > > > Should this message be altered to mention things like what this patch > > > does? > > > > Thanks, I will rewrite the message in next version. > > > > > > > qemu-system-riscv64: vhost_set_mem_table failed: Interrupted system > > > > call (4) > > > > qemu-system-riscv64: unable to start vhost net: 4: falling back on > > > > userspace virtio > > > > > > > > Note that, before starting the kvm-acceled QEMU VM, following > > > > temporarily unaccepted QEMU patches should be used: > > > > https://lists.gnu.org/archive/html/qemu-devel/2021-08/msg02516.html > > > > > > > > This error was made bacause default main_mem is used to be registered > > > > > > typo: because > > > > > Thanks. > > > > > > as the system memory, other memory cannot be initialized. Therefore, > > > > the system memory should be initialized to the machine->ram, which > > > > consists of the default main_mem and other possible memory required by > > > > applications, such as shared hugepage memory in DPDK. > > > > Also, the mc->defaul_ram_id should be set to the default main_mem, > > > > such as "riscv_virt_board.ram" for the virt machine. > > > > > > > > > > How about changing the commit title to: "Use machine->ram as the system > > > memory" ?? > > > > > > > I think it is just a bugfix. > > > > But the current codes run perfectly okay so far. This patch adds an > additional use case for the KVM scenario where current codes
Re: [PATCH v2] hw/riscv: virt: bugfix the memory-backend-file command is invalid
On Fri, Oct 15, 2021 at 4:52 PM limingwang (A) wrote: > > > On Wed, Oct 13, 2021 at 22:41 PM Bin Meng wrote: > > > > On Tue, Oct 12, 2021 at 9:46 AM MingWang Li wrote: > > > > > > From: Mingwang Li > > > > > > When I start the VM with the following command: > > > $ ./qemu-system-riscv64 -M virt,accel=kvm -m 4096M -cpu host -nographic \ > > > -name guest=riscv-guset \ > > > -smp 2 \ > > > -bios none \ > > > -kernel ./Image \ > > > -drive file=./guest.img,format=raw,id=hd0 \ > > > -device virtio-blk-device,drive=hd0 \ > > > -append "root=/dev/vda rw console=ttyS0 earlycon=sbi" \ > > > -object > > memory-backend-file,id=mem,size=4096M,mem-path=/dev/hugepages,share=on \ > > > -numa node,memdev=mem -mem-prealloc \ > > > -chardev socket,id=char0,path=/mnt/vhost-net0 \ > > > -netdev type=vhost-user,id=mynet1,chardev=char0,vhostforce \ > > > -device > > > virtio-net-pci,mac=52:54:00:00:00:01,netdev=mynet1,mrg_rxbuf=on,csum=o > > > n,guest_csum=on,guest_ecn=on \ > > > > > > Then, QEMU displays the following error information: > > > qemu-system-riscv64: Failed initializing vhost-user memory map, > > > consider using -object memory-backend-file share=on > > > > I see your command line parameters already contain "-object > > memory-backend-file > > share=on", so this error message is not accurate. > > QEMU uses this command to alloc fd in the "memory_region_init_ram_from_file" > function > and assigns the value of fd to mr->ram_block-fd. If the QEMU uses the default > memory to > initialize the system, the QEMU cannot obtain the fd in the > "vhost_user_mem_section_filter" > function when initializing the vhost-user. As a result, an error is reported > in the "vhost_user_fill_set_mem_table_msg" > function. > > Because of the above bug, even if "-object memory-backend-file share=on" is > added to the command line, > the QEMU still reports an error. Yes, what I meant is that QEMU should not report such inaccurate messages because of some random codes elsewhere. With current message, it suggested user use "-object memory-backend-file share=on" in the command line, but it is already used. So this is a false alarm. The "bug" is somewhere else. > This patch can solve this bug. > > > Should this message be altered to mention things like what this patch does? > > Thanks, I will rewrite the message in next version. > > > > > qemu-system-riscv64: vhost_set_mem_table failed: Interrupted system > > > call (4) > > > qemu-system-riscv64: unable to start vhost net: 4: falling back on > > > userspace virtio > > > > > > Note that, before starting the kvm-acceled QEMU VM, following > > > temporarily unaccepted QEMU patches should be used: > > > https://lists.gnu.org/archive/html/qemu-devel/2021-08/msg02516.html > > > > > > This error was made bacause default main_mem is used to be registered > > > > typo: because > > > Thanks. > > > > as the system memory, other memory cannot be initialized. Therefore, > > > the system memory should be initialized to the machine->ram, which > > > consists of the default main_mem and other possible memory required by > > > applications, such as shared hugepage memory in DPDK. > > > Also, the mc->defaul_ram_id should be set to the default main_mem, > > > such as "riscv_virt_board.ram" for the virt machine. > > > > > > > How about changing the commit title to: "Use machine->ram as the system > > memory" ?? > > > > I think it is just a bugfix. > But the current codes run perfectly okay so far. This patch adds an additional use case for the KVM scenario where current codes cannot handle. Regards, Bin
RE: [PATCH v2] hw/riscv: virt: bugfix the memory-backend-file command is invalid
On Wed, Oct 13, 2021 at 22:41 PM Bin Meng wrote: > > On Tue, Oct 12, 2021 at 9:46 AM MingWang Li wrote: > > > > From: Mingwang Li > > > > When I start the VM with the following command: > > $ ./qemu-system-riscv64 -M virt,accel=kvm -m 4096M -cpu host -nographic \ > > -name guest=riscv-guset \ > > -smp 2 \ > > -bios none \ > > -kernel ./Image \ > > -drive file=./guest.img,format=raw,id=hd0 \ > > -device virtio-blk-device,drive=hd0 \ > > -append "root=/dev/vda rw console=ttyS0 earlycon=sbi" \ > > -object > memory-backend-file,id=mem,size=4096M,mem-path=/dev/hugepages,share=on \ > > -numa node,memdev=mem -mem-prealloc \ > > -chardev socket,id=char0,path=/mnt/vhost-net0 \ > > -netdev type=vhost-user,id=mynet1,chardev=char0,vhostforce \ > > -device > > virtio-net-pci,mac=52:54:00:00:00:01,netdev=mynet1,mrg_rxbuf=on,csum=o > > n,guest_csum=on,guest_ecn=on \ > > > > Then, QEMU displays the following error information: > > qemu-system-riscv64: Failed initializing vhost-user memory map, > > consider using -object memory-backend-file share=on > > I see your command line parameters already contain "-object > memory-backend-file > share=on", so this error message is not accurate. QEMU uses this command to alloc fd in the "memory_region_init_ram_from_file" function and assigns the value of fd to mr->ram_block-fd. If the QEMU uses the default memory to initialize the system, the QEMU cannot obtain the fd in the "vhost_user_mem_section_filter" function when initializing the vhost-user. As a result, an error is reported in the "vhost_user_fill_set_mem_table_msg" function. Because of the above bug, even if "-object memory-backend-file share=on" is added to the command line, the QEMU still reports an error. This patch can solve this bug. > Should this message be altered to mention things like what this patch does? Thanks, I will rewrite the message in next version. > > > qemu-system-riscv64: vhost_set_mem_table failed: Interrupted system > > call (4) > > qemu-system-riscv64: unable to start vhost net: 4: falling back on > > userspace virtio > > > > Note that, before starting the kvm-acceled QEMU VM, following > > temporarily unaccepted QEMU patches should be used: > > https://lists.gnu.org/archive/html/qemu-devel/2021-08/msg02516.html > > > > This error was made bacause default main_mem is used to be registered > > typo: because > Thanks. > > as the system memory, other memory cannot be initialized. Therefore, > > the system memory should be initialized to the machine->ram, which > > consists of the default main_mem and other possible memory required by > > applications, such as shared hugepage memory in DPDK. > > Also, the mc->defaul_ram_id should be set to the default main_mem, > > such as "riscv_virt_board.ram" for the virt machine. > > > > How about changing the commit title to: "Use machine->ram as the system > memory" ?? > I think it is just a bugfix. > > Signed-off-by: Mingwang Li > > Signed-off-by: Yifei Jiang > > Reviewed-by: Alistair Francis > > --- > > hw/riscv/virt.c | 6 ++ > > 1 file changed, 2 insertions(+), 4 deletions(-) > > > > diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c index > > ec0cb69b8c..b3b431c847 100644 > > --- a/hw/riscv/virt.c > > +++ b/hw/riscv/virt.c > > @@ -771,7 +771,6 @@ static void virt_machine_init(MachineState *machine) > > const MemMapEntry *memmap = virt_memmap; > > RISCVVirtState *s = RISCV_VIRT_MACHINE(machine); > > MemoryRegion *system_memory = get_system_memory(); > > -MemoryRegion *main_mem = g_new(MemoryRegion, 1); > > MemoryRegion *mask_rom = g_new(MemoryRegion, 1); > > char *plic_hart_config, *soc_name; > > target_ulong start_addr = memmap[VIRT_DRAM].base; @@ -890,10 > > +889,8 @@ static void virt_machine_init(MachineState *machine) > > } > > > > /* register system main memory (actual RAM) */ > > -memory_region_init_ram(main_mem, NULL, "riscv_virt_board.ram", > > - machine->ram_size, _fatal); > > memory_region_add_subregion(system_memory, > memmap[VIRT_DRAM].base, > > -main_mem); > > +machine->ram); > > > > /* create device tree */ > > create_fdt(s, memmap, machine->ram_size, machine->kernel_cmdline, > > @@ -1032,6 +1029,7 @@ static void virt_machine_class_init(ObjectClass *oc, > void *data) > > mc->cpu_index_to_instance_props = riscv_numa_cpu_index_to_props; > > mc->get_default_cpu_node_id = riscv_numa_get_default_cpu_node_id; > > mc->numa_mem_supported = true; > > +mc->default_ram_id = "riscv_virt_board.ram"; > > > > machine_class_allow_dynamic_sysbus_dev(mc, TYPE_RAMFB_DEVICE); > > > > Regards, > Bin
Re: [PATCH v2] hw/riscv: virt: bugfix the memory-backend-file command is invalid
On Tue, Oct 12, 2021 at 9:46 AM MingWang Li wrote: > > From: Mingwang Li > > When I start the VM with the following command: > $ ./qemu-system-riscv64 -M virt,accel=kvm -m 4096M -cpu host -nographic \ > -name guest=riscv-guset \ > -smp 2 \ > -bios none \ > -kernel ./Image \ > -drive file=./guest.img,format=raw,id=hd0 \ > -device virtio-blk-device,drive=hd0 \ > -append "root=/dev/vda rw console=ttyS0 earlycon=sbi" \ > -object > memory-backend-file,id=mem,size=4096M,mem-path=/dev/hugepages,share=on \ > -numa node,memdev=mem -mem-prealloc \ > -chardev socket,id=char0,path=/mnt/vhost-net0 \ > -netdev type=vhost-user,id=mynet1,chardev=char0,vhostforce \ > -device > virtio-net-pci,mac=52:54:00:00:00:01,netdev=mynet1,mrg_rxbuf=on,csum=on,guest_csum=on,guest_ecn=on > \ > > Then, QEMU displays the following error information: > qemu-system-riscv64: Failed initializing vhost-user memory map, consider > using -object memory-backend-file share=on I see your command line parameters already contain "-object memory-backend-file share=on", so this error message is not accurate. Should this message be altered to mention things like what this patch does? > qemu-system-riscv64: vhost_set_mem_table failed: Interrupted system call (4) > qemu-system-riscv64: unable to start vhost net: 4: falling back on userspace > virtio > > Note that, before starting the kvm-acceled QEMU VM, following > temporarily unaccepted QEMU patches should be used: > https://lists.gnu.org/archive/html/qemu-devel/2021-08/msg02516.html > > This error was made bacause default main_mem is used to be registered typo: because > as the system memory, other memory cannot be initialized. Therefore, > the system memory should be initialized to the machine->ram, which > consists of the default main_mem and other possible memory required > by applications, such as shared hugepage memory in DPDK. > Also, the mc->defaul_ram_id should be set to the default main_mem, > such as "riscv_virt_board.ram" for the virt machine. > How about changing the commit title to: "Use machine->ram as the system memory" ?? > Signed-off-by: Mingwang Li > Signed-off-by: Yifei Jiang > Reviewed-by: Alistair Francis > --- > hw/riscv/virt.c | 6 ++ > 1 file changed, 2 insertions(+), 4 deletions(-) > > diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c > index ec0cb69b8c..b3b431c847 100644 > --- a/hw/riscv/virt.c > +++ b/hw/riscv/virt.c > @@ -771,7 +771,6 @@ static void virt_machine_init(MachineState *machine) > const MemMapEntry *memmap = virt_memmap; > RISCVVirtState *s = RISCV_VIRT_MACHINE(machine); > MemoryRegion *system_memory = get_system_memory(); > -MemoryRegion *main_mem = g_new(MemoryRegion, 1); > MemoryRegion *mask_rom = g_new(MemoryRegion, 1); > char *plic_hart_config, *soc_name; > target_ulong start_addr = memmap[VIRT_DRAM].base; > @@ -890,10 +889,8 @@ static void virt_machine_init(MachineState *machine) > } > > /* register system main memory (actual RAM) */ > -memory_region_init_ram(main_mem, NULL, "riscv_virt_board.ram", > - machine->ram_size, _fatal); > memory_region_add_subregion(system_memory, memmap[VIRT_DRAM].base, > -main_mem); > +machine->ram); > > /* create device tree */ > create_fdt(s, memmap, machine->ram_size, machine->kernel_cmdline, > @@ -1032,6 +1029,7 @@ static void virt_machine_class_init(ObjectClass *oc, > void *data) > mc->cpu_index_to_instance_props = riscv_numa_cpu_index_to_props; > mc->get_default_cpu_node_id = riscv_numa_get_default_cpu_node_id; > mc->numa_mem_supported = true; > +mc->default_ram_id = "riscv_virt_board.ram"; > > machine_class_allow_dynamic_sysbus_dev(mc, TYPE_RAMFB_DEVICE); > Regards, Bin
[PATCH v2] hw/riscv: virt: bugfix the memory-backend-file command is invalid
From: Mingwang Li When I start the VM with the following command: $ ./qemu-system-riscv64 -M virt,accel=kvm -m 4096M -cpu host -nographic \ -name guest=riscv-guset \ -smp 2 \ -bios none \ -kernel ./Image \ -drive file=./guest.img,format=raw,id=hd0 \ -device virtio-blk-device,drive=hd0 \ -append "root=/dev/vda rw console=ttyS0 earlycon=sbi" \ -object memory-backend-file,id=mem,size=4096M,mem-path=/dev/hugepages,share=on \ -numa node,memdev=mem -mem-prealloc \ -chardev socket,id=char0,path=/mnt/vhost-net0 \ -netdev type=vhost-user,id=mynet1,chardev=char0,vhostforce \ -device virtio-net-pci,mac=52:54:00:00:00:01,netdev=mynet1,mrg_rxbuf=on,csum=on,guest_csum=on,guest_ecn=on \ Then, QEMU displays the following error information: qemu-system-riscv64: Failed initializing vhost-user memory map, consider using -object memory-backend-file share=on qemu-system-riscv64: vhost_set_mem_table failed: Interrupted system call (4) qemu-system-riscv64: unable to start vhost net: 4: falling back on userspace virtio Note that, before starting the kvm-acceled QEMU VM, following temporarily unaccepted QEMU patches should be used: https://lists.gnu.org/archive/html/qemu-devel/2021-08/msg02516.html This error was made bacause default main_mem is used to be registered as the system memory, other memory cannot be initialized. Therefore, the system memory should be initialized to the machine->ram, which consists of the default main_mem and other possible memory required by applications, such as shared hugepage memory in DPDK. Also, the mc->defaul_ram_id should be set to the default main_mem, such as "riscv_virt_board.ram" for the virt machine. Signed-off-by: Mingwang Li Signed-off-by: Yifei Jiang Reviewed-by: Alistair Francis --- hw/riscv/virt.c | 6 ++ 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c index ec0cb69b8c..b3b431c847 100644 --- a/hw/riscv/virt.c +++ b/hw/riscv/virt.c @@ -771,7 +771,6 @@ static void virt_machine_init(MachineState *machine) const MemMapEntry *memmap = virt_memmap; RISCVVirtState *s = RISCV_VIRT_MACHINE(machine); MemoryRegion *system_memory = get_system_memory(); -MemoryRegion *main_mem = g_new(MemoryRegion, 1); MemoryRegion *mask_rom = g_new(MemoryRegion, 1); char *plic_hart_config, *soc_name; target_ulong start_addr = memmap[VIRT_DRAM].base; @@ -890,10 +889,8 @@ static void virt_machine_init(MachineState *machine) } /* register system main memory (actual RAM) */ -memory_region_init_ram(main_mem, NULL, "riscv_virt_board.ram", - machine->ram_size, _fatal); memory_region_add_subregion(system_memory, memmap[VIRT_DRAM].base, -main_mem); +machine->ram); /* create device tree */ create_fdt(s, memmap, machine->ram_size, machine->kernel_cmdline, @@ -1032,6 +1029,7 @@ static void virt_machine_class_init(ObjectClass *oc, void *data) mc->cpu_index_to_instance_props = riscv_numa_cpu_index_to_props; mc->get_default_cpu_node_id = riscv_numa_get_default_cpu_node_id; mc->numa_mem_supported = true; +mc->default_ram_id = "riscv_virt_board.ram"; machine_class_allow_dynamic_sysbus_dev(mc, TYPE_RAMFB_DEVICE); -- 2.19.1
