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Diffstat (limited to 'results/classifier/deepseek-2-tmp/reasoning/mistranslation/1587535')
| -rw-r--r-- | results/classifier/deepseek-2-tmp/reasoning/mistranslation/1587535 | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/results/classifier/deepseek-2-tmp/reasoning/mistranslation/1587535 b/results/classifier/deepseek-2-tmp/reasoning/mistranslation/1587535 new file mode 100644 index 00000000..555fa7c0 --- /dev/null +++ b/results/classifier/deepseek-2-tmp/reasoning/mistranslation/1587535 @@ -0,0 +1,19 @@ +<think> +Okay, let me try to figure out the category for this bug report. So, the issue is about an incorrect TLB entry size in QEMU when booting multi-core e500 PPC systems. The problem occurs because of a miscalculation in how the TLB size is determined. + +Looking at the code snippets provided, it mentions that booke206_page_size_to_tlb() uses ctz32(size >> 10) and then right-shifts by another bit (>>1). This effectively divides the size by 4, but the problem is that MAS1_TSIZE_SHIFT was defined expecting a different shift. It should be using shift=8 instead of shift=7 because the calculation assumes n^4 * 1KB for newer PPC cores, while the existing code treats it as n^2 * 1KB. + +So, this seems to be an issue with how the TLB size is being computed and mapped in the QEMU code. The function booke206_page_size_to_tlb() is part of the translation process from user-mode assembly (like PPC) to the target architecture's TLB handling. Therefore, it falls under 'mistranslation' because there's an incorrect semantic mapping leading to a wrong TLB entry size. + +I think other categories like 'assembly' might be close, but since it's more about the translation and not the assembly lowering itself, 'mistranslation' is the right fit. +</think> + +The bug report involves an error in how the TLB (Translation Lookaside Buffer) size is calculated for PPC e500 cores in QEMU. The function `booke206_page_size_to_tlb` incorrectly shifts the page size, leading to a smaller TLB entry than intended. This issue stems from a miscalculation due to a mismatch between expected and actual shift values in the code. + +The problem occurs during the creation of initial memory mappings when non-boot cores are started via the spin table. The function `mmubooke_create_initial_mapping` is supposed to allocate a 64MB TLB entry but ends up with only 256KB because of an incorrect shift operation in `booke206_page_size_to_tlb`. + +This issue relates to how the QEMU code translates user-mode assembly (specifically PPC) into the target architecture's TLB handling. The incorrect calculation is a result of a misalignment between the assumed and actual TLB entry size computation, which falls under the category of 'mistranslation' as it involves an incorrect semantic mapping from the source architecture to the target. + +**Answer:** + +mistranslation \ No newline at end of file |