linux-dev/arch/arm64/kvm/vgic, branch master

KVM: arm64: vgic: Fix exit condition in scan_its_table()

2022-10-15T11:10:54Z

With some PCIe topologies, restoring a guest fails while parsing the ITS device tables. Reproducer hints: 1. Create ARM virt VM with pxb-pcie bus which adds extra host bridges, with qemu command like: ``` -device pxb-pcie,bus_nr=8,id=pci.x,numa_node=0,bus=pcie.0 \ -device pcie-root-port,..,bus=pci.x \ ... -device pxb-pcie,bus_nr=37,id=pci.y,numa_node=1,bus=pcie.0 \ -device pcie-root-port,..,bus=pci.y \ ... ``` 2. Ensure the guest uses 2-level device table 3. Perform VM migration which calls save/restore device tables In that setup, we get a big "offset" between 2 device_ids, which makes unsigned "len" round up a big positive number, causing the scan loop to continue with a bad GPA. For example: 1. L1 table has 2 entries; 2. and we are now scanning at L2 table entry index 2075 (pointed to by L1 first entry) 3. if next device id is 9472, we will get a big offset: 7397; 4. with unsigned 'len', 'len -= offset * esz', len will underflow to a positive number, mistakenly into next iteration with a bad GPA; (It should break out of the current L2 table scanning, and jump into the next L1 table entry) 5. that bad GPA fails the guest read. Fix it by stopping the L2 table scan when the next device id is outside of the current table, allowing the scan to continue from the next L1 table entry. Thanks to Eric Auger for the fix suggestion. Fixes: 920a7a8fa92a ("KVM: arm64: vgic-its: Add infrastructure for tableookup") Suggested-by: Eric Auger Signed-off-by: Eric Ren [maz: commit message tidy-up] Signed-off-by: Marc Zyngier Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/d9c3a564af9e2c5bf63f48a7dcbf08cd593c5c0b.1665802985.git.renzhengeek@gmail.com

KVM: arm64: vgic: Remove duplicate check in update_affinity_collection()

2022-09-26T09:46:37Z

The 'coll' parameter to update_affinity_collection() is never NULL, so comparing it with 'ite->collection' is enough to cover both the NULL case and the "another collection" case. Remove the duplicate check in update_affinity_collection(). Signed-off-by: Gavin Shan [maz: repainted commit message] Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20220923065447.323445-1-gshan@redhat.com

KVM: arm64: vgic: Tidy-up calls to vgic_{get,set}_common_attr()

2022-07-17T10:55:33Z

The userspace accessors have an early call to vgic_{get,set}_common_attr() that makes the code hard to follow. Move it to the default: clause of the decoding switch statement, which results in a nice cleanup. This requires us to move the handling of the pending table into the common handling, even if it is strictly a GICv3 feature (it has the benefit of keeping the whole control group handling in the same function). Also cleanup vgic_v3_{get,set}_attr() while we're at it, deduplicating the calls to vgic_v3_attr_regs_access(). Suggested-by: Reiji Watanabe Signed-off-by: Marc Zyngier

KVM: arm64: vgic: Consolidate userspace access for base address setting

2022-07-17T10:55:33Z

Align kvm_vgic_addr() with the rest of the code by moving the userspace accesses into it. kvm_vgic_addr() is also made static. Signed-off-by: Marc Zyngier

KVM: arm64: vgic-v2: Add helper for legacy dist/cpuif base address setting

2022-07-17T10:55:33Z

We carry a legacy interface to set the base addresses for GICv2. As this is currently plumbed into the same handling code as the modern interface, it limits the evolution we can make there. Add a helper dedicated to this handling, with a view of maybe removing this in the future. Signed-off-by: Marc Zyngier

KVM: arm64: vgic: Use {get,put}_user() instead of copy_{from.to}_user

2022-07-17T10:55:33Z

Tidy-up vgic_get_common_attr() and vgic_set_common_attr() to use {get,put}_user() instead of the more complex (and less type-safe) copy_{from,to}_user(). Reviewed-by: Reiji Watanabe Signed-off-by: Marc Zyngier

KVM: arm64: vgic-v2: Consolidate userspace access for MMIO registers

2022-07-17T10:55:33Z

Align the GICv2 MMIO accesses from userspace with the way the GICv3 code is now structured. Reviewed-by: Reiji Watanabe Signed-off-by: Marc Zyngier

KVM: arm64: vgic-v3: Consolidate userspace access for MMIO registers

2022-07-17T10:55:33Z

For userspace accesses to GICv3 MMIO registers (and related data), vgic_v3_{get,set}_attr are littered with {get,put}_user() calls, making it hard to audit and reason about. Consolidate all userspace accesses in vgic_v3_attr_regs_access(), making the code far simpler to audit. Reviewed-by: Reiji Watanabe Signed-off-by: Marc Zyngier

KVM: arm64: vgic-v3: Use u32 to manage the line level from userspace

2022-07-17T10:55:33Z

Despite the userspace ABI clearly defining the bits dealt with by KVM_DEV_ARM_VGIC_GRP_LEVEL_INFO as a __u32, the kernel uses a u64. Use a u32 to match the userspace ABI, which will subsequently lead to some simplifications. Reviewed-by: Reiji Watanabe Signed-off-by: Marc Zyngier

KVM: arm64: vgic-v3: Push user access into vgic_v3_cpu_sysregs_uaccess()

2022-07-17T10:55:33Z

In order to start making the vgic sysreg access from userspace similar to all the other sysregs, push the userspace memory access one level down into vgic_v3_cpu_sysregs_uaccess(). The next step will be to rely on the sysreg infrastructure to perform this task. Reviewed-by: Reiji Watanabe Signed-off-by: Marc Zyngier