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  1. JDK
  2. JDK-8238596

AVX enabled by default for Skylake even when unsupported

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      Description

        The fix for jdk-8221092 causes UseAVX to default to 2 for Skylake server CPUs (CPUID Model 0x55) even in environments where AVX support is not enabled. This causes HotSpot to crash with an SIGILL.

        While the Skylake hardware may support several of the AVX extensions, AVX support is often disabled when using a hypervisor. For example, some older (but still officially supported) hypervisors do not have support for XSAVE and therefor disable AVX to ensure they do not corrupt anything. As another example, I was able to reproduce this crash by disabling nested paging on VirtualBox (which also results in AVX being disabled) and running "java -version".

        While this can be worked around by setting UseAVX=0, the fact that HotSpot now crashes OOTB in these environments is a serious regression that needs to be fixed.

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            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8238743 AVX enabled by default for Skylake even when unsupported

            • P2 - Crashes, loss of data, severe memory leak.
            • Resolved

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8239057 AVX enabled by default for Skylake even when unsupported

            • P2 - Crashes, loss of data, severe memory leak.
            • Resolved

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8239442 AVX enabled by default for Skylake even when unsupported

            • P2 - Crashes, loss of data, severe memory leak.
            • Resolved

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8239933 AVX enabled by default for Skylake even when unsupported

            • P2 - Crashes, loss of data, severe memory leak.
            • Resolved

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8241573 AVX enabled by default for Skylake even when unsupported

            • P2 - Crashes, loss of data, severe memory leak.
            • Resolved

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8243313 AVX enabled by default for Skylake even when unsupported

            • P2 - Crashes, loss of data, severe memory leak.
            • Resolved

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8238883 AVX enabled by default for Skylake even when unsupported

            • P2 - Crashes, loss of data, severe memory leak.
            • Closed

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8239587 AVX enabled by default for Skylake even when unsupported

            • P2 - Crashes, loss of data, severe memory leak.
            • Closed
            relates to

            Bug - A problem which impairs or prevents the functions of the product. JDK-8221092 UseAVX=3 has performance degredation on Skylake (X7) processors

            • P3 - Major loss of function.
            • Resolved

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                dbuck David Buck
                shadowbug Shadow Bug
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                  Updated:
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