kernel/linux.git/drivers/hv/hv.c, branch v6.4

Drivers: hv: move panic report code from vmbus to hv early init code

2023-04-20T23:00:37+00:00

The panic reporting code was added in commit 81b18bce48af ("Drivers: HV: Send one page worth of kmsg dump over Hyper-V during panic") It was added to the vmbus driver. The panic reporting has no dependence on vmbus, and can be enabled at an earlier boot time when Hyper-V is initialized. This patch moves the panic reporting code out of vmbus. There is no functionality changes. During moving, also refactored some cleanup functions into hv_kmsg_dump_unregister(). Signed-off-by: Long Li Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/1682030946-6372-1-git-send-email-longli@linuxonhyperv.com Signed-off-by: Wei Liu

Drivers: hv: vmbus: Remove the per-CPU post_msg_page

2023-04-17T19:19:05+00:00

The post_msg_page was introduced in 2014 in commit b29ef3546aec ("Drivers: hv: vmbus: Cleanup hv_post_message()") Commit 68bb7bfb7985 ("X86/Hyper-V: Enable IPI enlightenments") introduced the hyperv_pcpu_input_arg in 2018, which can be used in hv_post_message(). Remove post_msg_page to simplify the code a little bit. Signed-off-by: Dexuan Cui Reviewed-by: Jinank Jain Link: https://lore.kernel.org/r/20230408213441.15472-1-decui@microsoft.com Signed-off-by: Wei Liu

Drivers: hv: Don't remap addresses that are above shared_gpa_boundary

2023-04-17T19:19:04+00:00

With the vTOM bit now treated as a protection flag and not part of the physical address, avoid remapping physical addresses with vTOM set since technically such addresses aren't valid. Use ioremap_cache() instead of memremap() to ensure that the mapping provides decrypted access, which will correctly set the vTOM bit as a protection flag. While this change is not required for correctness with the current implementation of memremap(), for general code hygiene it's better to not depend on the mapping functions doing something reasonable with a physical address that is out-of-range. While here, fix typos in two error messages. Signed-off-by: Michael Kelley Reviewed-by: Tianyu Lan Link: https://lore.kernel.org/r/1679838727-87310-12-git-send-email-mikelley@microsoft.com Signed-off-by: Wei Liu

Drivers: hv: Setup synic registers in case of nested root partition

2023-01-17T13:36:43+00:00

Child partitions are free to allocate SynIC message and event page but in case of root partition it must use the pages allocated by Microsoft Hypervisor (MSHV). Base address for these pages can be found using synthetic MSRs exposed by MSHV. There is a slight difference in those MSRs for nested vs non-nested root partition. Signed-off-by: Jinank Jain Reviewed-by: Nuno Das Neves Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/cb951fb1ad6814996fc54f4a255c5841a20a151f.1672639707.git.jinankjain@linux.microsoft.com Signed-off-by: Wei Liu

x86/hyperv: Add ghcb hvcall support for SNP VM

2021-10-28T11:22:49+00:00

hyperv provides ghcb hvcall to handle VMBus HVCALL_SIGNAL_EVENT and HVCALL_POST_MESSAGE msg in SNP Isolation VM. Add such support. Reviewed-by: Michael Kelley Signed-off-by: Tianyu Lan Link: https://lore.kernel.org/r/20211025122116.264793-8-ltykernel@gmail.com Signed-off-by: Wei Liu

x86/hyperv: Add Write/Read MSR registers via ghcb page

2021-10-28T11:22:38+00:00

Hyperv provides GHCB protocol to write Synthetic Interrupt Controller MSR registers in Isolation VM with AMD SEV SNP and these registers are emulated by hypervisor directly. Hyperv requires to write SINTx MSR registers twice. First writes MSR via GHCB page to communicate with hypervisor and then writes wrmsr instruction to talk with paravisor which runs in VMPL0. Guest OS ID MSR also needs to be set via GHCB page. Reviewed-by: Michael Kelley Signed-off-by: Tianyu Lan Link: https://lore.kernel.org/r/20211025122116.264793-7-ltykernel@gmail.com Signed-off-by: Wei Liu

drivers: hv: Create a consistent pattern for checking Hyper-V hypercall status

2021-04-21T09:49:19+00:00

There is not a consistent pattern for checking Hyper-V hypercall status. Existing code uses a number of variants. The variants work, but a consistent pattern would improve the readability of the code, and be more conformant to what the Hyper-V TLFS says about hypercall status. Implemented new helper functions hv_result(), hv_result_success(), and hv_repcomp(). Changed the places where hv_do_hypercall() and related variants are used to use the helper functions. Signed-off-by: Joseph Salisbury Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/1618620183-9967-2-git-send-email-joseph.salisbury@linux.microsoft.com Signed-off-by: Wei Liu

Drivers: hv: vmbus: Check for pending channel interrupts before taking a CPU offline

2021-04-18T13:03:11+00:00

Check that enough time has passed such that the modify channel message has been processed before taking a CPU offline. Signed-off-by: Andrea Parri (Microsoft) Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/20210416143449.16185-4-parri.andrea@gmail.com Signed-off-by: Wei Liu

Drivers: hv: vmbus: Remove unused linux/version.h header

2021-04-02T22:09:46+00:00

That file is not needed in hv.c. Reported-by: Hulk Robot Signed-off-by: Qiheng Lin Link: https://lore.kernel.org/r/20210331060646.2471-1-linqiheng@huawei.com Signed-off-by: Wei Liu

Drivers: hv: vmbus: Move handling of VMbus interrupts

2021-03-08T17:33:00+00:00

VMbus interrupts are most naturally modelled as per-cpu IRQs. But because x86/x64 doesn't have per-cpu IRQs, the core VMbus interrupt handling machinery is done in code under arch/x86 and Linux IRQs are not used. Adding support for ARM64 means adding equivalent code using per-cpu IRQs under arch/arm64. A better model is to treat per-cpu IRQs as the normal path (which it is for modern architectures), and the x86/x64 path as the exception. Do this by incorporating standard Linux per-cpu IRQ allocation into the main VMbus driver, and bypassing it in the x86/x64 exception case. For x86/x64, special case code is retained under arch/x86, but no VMbus interrupt handling code is needed under arch/arm64. No functional change. Signed-off-by: Michael Kelley Reviewed-by: Boqun Feng Link: https://lore.kernel.org/r/1614721102-2241-7-git-send-email-mikelley@microsoft.com Signed-off-by: Wei Liu