From: Michael Kelley <[email protected]> The Hyper-V ISRs, for normal guests and when running in the hypervisor root patition, are calling add_interrupt_randomness() as a primary source of entropy. The call is currently in the ISRs as a common place to handle both x86/x64 and arm64. On x86/x64, hypervisor interrupts come through a custom sysvec entry, and do not go through a generic interrupt handler. On arm64, hypervisor interrupts come through an emulated GICv3. GICv3 uses the generic handler handle_percpu_devid_irq(), which does not do add_interrupt_randomness() -- unlike its counterpart handle_percpu_irq(). But handle_percpu_devid_irq() is now updated to do the add_interrupt_randomness(). So add_interrupt_randomness() is now needed only in Hyper-V's x86/x64 custom sysvec path.
Move add_interrupt_randomness() from the Hyper-V ISRs into the Hyper-V x86/x64 custom sysvec path, matching the existing STIMER0 sysvec path. With this change, add_interrupt_randomness() is no longer called from any device drivers, which is appropriate. Signed-off-by: Michael Kelley <[email protected]> --- arch/x86/kernel/cpu/mshyperv.c | 2 ++ drivers/hv/mshv_synic.c | 3 --- drivers/hv/vmbus_drv.c | 3 --- 3 files changed, 2 insertions(+), 6 deletions(-) diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c index 9befdc557d9e..a7dfc29d3470 100644 --- a/arch/x86/kernel/cpu/mshyperv.c +++ b/arch/x86/kernel/cpu/mshyperv.c @@ -161,6 +161,8 @@ DEFINE_IDTENTRY_SYSVEC(sysvec_hyperv_callback) if (vmbus_handler) vmbus_handler(); + add_interrupt_randomness(HYPERVISOR_CALLBACK_VECTOR); + if (ms_hyperv.hints & HV_DEPRECATING_AEOI_RECOMMENDED) apic_eoi(); diff --git a/drivers/hv/mshv_synic.c b/drivers/hv/mshv_synic.c index 43f1bcbbf2d3..e2288a726fec 100644 --- a/drivers/hv/mshv_synic.c +++ b/drivers/hv/mshv_synic.c @@ -12,7 +12,6 @@ #include <linux/mm.h> #include <linux/interrupt.h> #include <linux/io.h> -#include <linux/random.h> #include <linux/cpuhotplug.h> #include <linux/reboot.h> #include <asm/mshyperv.h> @@ -445,8 +444,6 @@ void mshv_isr(void) mb(); if (msg->header.message_flags.msg_pending) hv_set_non_nested_msr(HV_MSR_EOM, 0); - - add_interrupt_randomness(mshv_sint_vector); } else { pr_warn_once("%s: unknown message type 0x%x\n", __func__, msg->header.message_type); diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index 1d71c28fadba..3faa74e49a6b 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -32,7 +32,6 @@ #include <linux/ptrace.h> #include <linux/sysfb.h> #include <linux/efi.h> -#include <linux/random.h> #include <linux/kernel.h> #include <linux/syscore_ops.h> #include <linux/dma-map-ops.h> @@ -1356,8 +1355,6 @@ static void __vmbus_isr(void) vmbus_message_sched(hv_cpu, hv_cpu->hyp_synic_message_page); vmbus_message_sched(hv_cpu, hv_cpu->para_synic_message_page); - - add_interrupt_randomness(vmbus_interrupt); } static DEFINE_PER_CPU(bool, vmbus_irq_pending); -- 2.25.1
