On 20.09.23 06:52, Saurabh Sengar wrote: > There has been cases reported where HYPERV_VTL_MODE is enabled by mistake, > on a non Hyper-V platforms. This causes the hv_vtl_early_init function to > be called in an non Hyper-V/VTL platforms which results the memory > corruption. > > Remove the early_initcall for vhv_vtl_early_init and call it at the end of > hyperv_init to make sure it is never called in a non Hyper-V platform by > mistake. > > Reported-by: Mathias Krause <minipli@xxxxxxxxxxxxxx> > Closes: https://lore.kernel.org/lkml/40467722-f4ab-19a5-4989-308225b1f9f0@xxxxxxxxxxxxxx/ > Signed-off-by: Saurabh Sengar <ssengar@xxxxxxxxxxxxxxxxxxx> > --- > This patch is dependent on : > https://lore.kernel.org/lkml/1695182675-13405-1-git-send-email-ssengar@xxxxxxxxxxxxxxxxxxx/ > > arch/x86/hyperv/hv_init.c | 3 +++ > arch/x86/hyperv/hv_vtl.c | 3 +-- > arch/x86/include/asm/mshyperv.h | 2 ++ > 3 files changed, 6 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c > index f0128fd4031d..608f4fe41fb7 100644 > --- a/arch/x86/hyperv/hv_init.c > +++ b/arch/x86/hyperv/hv_init.c > @@ -610,6 +610,9 @@ void __init hyperv_init(void) > /* Find the VTL */ > ms_hyperv.vtl = get_vtl(); > > + if (ms_hyperv.vtl > 0) /* non default VTL */ > + hv_vtl_early_init(); > + As the kernel's console will already be initialized when this code gets executed, the possible panic() in hv_vtl_early_init() will actually be visible, thereby... > return; > > clean_guest_os_id: > diff --git a/arch/x86/hyperv/hv_vtl.c b/arch/x86/hyperv/hv_vtl.c > index 36a562218010..999f5ac82fe9 100644 > --- a/arch/x86/hyperv/hv_vtl.c > +++ b/arch/x86/hyperv/hv_vtl.c > @@ -215,7 +215,7 @@ static int hv_vtl_wakeup_secondary_cpu(int apicid, unsigned long start_eip) > return hv_vtl_bringup_vcpu(vp_id, start_eip); > } > > -static int __init hv_vtl_early_init(void) > +int __init hv_vtl_early_init(void) > { > /* > * `boot_cpu_has` returns the runtime feature support, > @@ -230,4 +230,3 @@ static int __init hv_vtl_early_init(void) > > return 0; > } > -early_initcall(hv_vtl_early_init); > diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h > index 033b53f993c6..83019c3aaae9 100644 > --- a/arch/x86/include/asm/mshyperv.h > +++ b/arch/x86/include/asm/mshyperv.h > @@ -340,8 +340,10 @@ static inline u64 hv_get_non_nested_register(unsigned int reg) { return 0; } > > #ifdef CONFIG_HYPERV_VTL_MODE > void __init hv_vtl_init_platform(void); > +int __init hv_vtl_early_init(void); > #else > static inline void __init hv_vtl_init_platform(void) {} > +static int __init hv_vtl_early_init(void) {} > #endif > > #include <asm-generic/mshyperv.h> Acked-by: Mathias Krause <minipli@xxxxxxxxxxxxxx> Thanks!
