| Message ID | 20220718141123.136106-1-mlevitsk@redhat.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | x86: cpuid: improve support for broken CPUID configurations | expand |
On Mon, 2022-07-18 at 17:11 +0300, Maxim Levitsky wrote: > This patch series aims to harden the cpuid code against the case when > the hypervisor exposes a broken CPUID configuration to the guest, > in the form of having a feature disabled but not features that depend on it. > > This is the more generic way to fix kernel panic in aes-ni kernel driver, > which was triggered by CPUID configuration in which AVX is disabled but > not AVX2. > > https://lore.kernel.org/all/20211103145231.GA4485@gondor.apana.org.au/T/ > > This was tested by booting a guest with AVX disabled and not AVX2, > and observing that both a warning is now printed in dmesg, and > that avx2 is gone from /proc/cpuinfo. > > V2: > > I hopefully addressed all the (very good) review feedback. > > Best regards, > Maxim Levitsky > > Maxim Levitsky (5): > perf/x86/intel/lbr: use setup_clear_cpu_cap instead of clear_cpu_cap > x86/cpuid: refactor setup_clear_cpu_cap()/clear_cpu_cap() > x86/cpuid: move filter_cpuid_features to cpuid-deps.c > x86/cpuid: remove 'warn' parameter from filter_cpuid_features > x86/cpuid: check for dependencies violations in CPUID and attempt to > fix them > > arch/x86/events/intel/lbr.c | 2 +- > arch/x86/include/asm/cpufeature.h | 1 + > arch/x86/kernel/cpu/common.c | 51 +------------------- > arch/x86/kernel/cpu/cpuid-deps.c | 80 +++++++++++++++++++++++++++---- > 4 files changed, 74 insertions(+), 60 deletions(-) > > -- > 2.34.3 > > A very kind ping on these patches. Best regards, Maxim Levitsky
On Thu, 2022-07-28 at 10:30 +0300, Maxim Levitsky wrote: > On Mon, 2022-07-18 at 17:11 +0300, Maxim Levitsky wrote: > > This patch series aims to harden the cpuid code against the case when > > the hypervisor exposes a broken CPUID configuration to the guest, > > in the form of having a feature disabled but not features that depend on it. > > > > This is the more generic way to fix kernel panic in aes-ni kernel driver, > > which was triggered by CPUID configuration in which AVX is disabled but > > not AVX2. > > > > https://lore.kernel.org/all/20211103145231.GA4485@gondor.apana.org.au/T/ > > > > This was tested by booting a guest with AVX disabled and not AVX2, > > and observing that both a warning is now printed in dmesg, and > > that avx2 is gone from /proc/cpuinfo. > > > > V2: > > > > I hopefully addressed all the (very good) review feedback. > > > > Best regards, > > Maxim Levitsky > > > > Maxim Levitsky (5): > > perf/x86/intel/lbr: use setup_clear_cpu_cap instead of clear_cpu_cap > > x86/cpuid: refactor setup_clear_cpu_cap()/clear_cpu_cap() > > x86/cpuid: move filter_cpuid_features to cpuid-deps.c > > x86/cpuid: remove 'warn' parameter from filter_cpuid_features > > x86/cpuid: check for dependencies violations in CPUID and attempt to > > fix them > > > > arch/x86/events/intel/lbr.c | 2 +- > > arch/x86/include/asm/cpufeature.h | 1 + > > arch/x86/kernel/cpu/common.c | 51 +------------------- > > arch/x86/kernel/cpu/cpuid-deps.c | 80 +++++++++++++++++++++++++++---- > > 4 files changed, 74 insertions(+), 60 deletions(-) > > > > -- > > 2.34.3 > > > > > A very kind ping on these patches. Another kind ping on these patches. Best regards, Maxim Levitsky > > Best regards, > Maxim Levitsky
On 8/1/22 09:05, Maxim Levitsky wrote: >> A very kind ping on these patches. > Another kind ping on these patches. Maxim, This series is not forgotten. Its latest version was simply posted too close to the merge window. It'll get looked at in a week or two when things calm down. Please be patient.
On Mon, 2022-08-01 at 09:31 -0700, Dave Hansen wrote: > On 8/1/22 09:05, Maxim Levitsky wrote: > > > A very kind ping on these patches. > > Another kind ping on these patches. > > Maxim, > > This series is not forgotten. Its latest version was simply posted too > close to the merge window. It'll get looked at in a week or two when > things calm down. > > Please be patient. > Thanks! Best regards, Maxim Levitsky
On Mon, 2022-08-01 at 19:05 +0300, Maxim Levitsky wrote: > On Thu, 2022-07-28 at 10:30 +0300, Maxim Levitsky wrote: > > On Mon, 2022-07-18 at 17:11 +0300, Maxim Levitsky wrote: > > > This patch series aims to harden the cpuid code against the case when > > > the hypervisor exposes a broken CPUID configuration to the guest, > > > in the form of having a feature disabled but not features that depend on it. > > > > > > This is the more generic way to fix kernel panic in aes-ni kernel driver, > > > which was triggered by CPUID configuration in which AVX is disabled but > > > not AVX2. > > > > > > https://lore.kernel.org/all/20211103145231.GA4485@gondor.apana.org.au/T/ > > > > > > This was tested by booting a guest with AVX disabled and not AVX2, > > > and observing that both a warning is now printed in dmesg, and > > > that avx2 is gone from /proc/cpuinfo. > > > > > > V2: > > > > > > I hopefully addressed all the (very good) review feedback. > > > > > > Best regards, > > > Maxim Levitsky > > > > > > Maxim Levitsky (5): > > > perf/x86/intel/lbr: use setup_clear_cpu_cap instead of clear_cpu_cap > > > x86/cpuid: refactor setup_clear_cpu_cap()/clear_cpu_cap() > > > x86/cpuid: move filter_cpuid_features to cpuid-deps.c > > > x86/cpuid: remove 'warn' parameter from filter_cpuid_features > > > x86/cpuid: check for dependencies violations in CPUID and attempt to > > > fix them > > > > > > arch/x86/events/intel/lbr.c | 2 +- > > > arch/x86/include/asm/cpufeature.h | 1 + > > > arch/x86/kernel/cpu/common.c | 51 +------------------- > > > arch/x86/kernel/cpu/cpuid-deps.c | 80 +++++++++++++++++++++++++++---- > > > 4 files changed, 74 insertions(+), 60 deletions(-) > > > > > > -- > > > 2.34.3 > > > > > > > > A very kind ping on these patches. > > Another kind ping on these patches. Another very gentle ping on these patches. Best regards, Maxim Levitsky > > > Best regards, > Maxim Levitsky > > Best regards, > > Maxim Levitsky
This patch series aims to harden the cpuid code against the case when the hypervisor exposes a broken CPUID configuration to the guest, in the form of having a feature disabled but not features that depend on it. This is the more generic way to fix kernel panic in aes-ni kernel driver, which was triggered by CPUID configuration in which AVX is disabled but not AVX2. https://lore.kernel.org/all/20211103145231.GA4485@gondor.apana.org.au/T/ This was tested by booting a guest with AVX disabled and not AVX2, and observing that both a warning is now printed in dmesg, and that avx2 is gone from /proc/cpuinfo. V2: I hopefully addressed all the (very good) review feedback. Best regards, Maxim Levitsky Maxim Levitsky (5): perf/x86/intel/lbr: use setup_clear_cpu_cap instead of clear_cpu_cap x86/cpuid: refactor setup_clear_cpu_cap()/clear_cpu_cap() x86/cpuid: move filter_cpuid_features to cpuid-deps.c x86/cpuid: remove 'warn' parameter from filter_cpuid_features x86/cpuid: check for dependencies violations in CPUID and attempt to fix them arch/x86/events/intel/lbr.c | 2 +- arch/x86/include/asm/cpufeature.h | 1 + arch/x86/kernel/cpu/common.c | 51 +------------------- arch/x86/kernel/cpu/cpuid-deps.c | 80 +++++++++++++++++++++++++++---- 4 files changed, 74 insertions(+), 60 deletions(-)