Core Viewpoint - The ongoing controversy surrounding Bcachefs, a file system recently accepted into the Linux kernel, highlights tensions between development practices and adherence to established protocols within the Linux community [1][3][5]. Group 1: Background of Bcachefs - Bcachefs was initiated by Kent Overstreet in 2015, aiming to combine the flexibility of Btrfs with the stability of ext4, featuring capabilities like copy-on-write, snapshots, compression, and checksumming [3]. - The project has been active as an external module for nearly a decade and was officially integrated into the Linux 6.7 kernel in early 2024 [3]. Group 2: Controversy and Development Practices - The recent dispute arose when Kent Overstreet submitted a new feature patch, journal_rewind, during the release candidate (RC) phase of Linux 6.16, which is against the established rule that only bug fixes are allowed at this stage [4][5]. - Linus Torvalds expressed strong discontent with this submission, emphasizing the importance of adhering to the merge window rules and labeling Bcachefs as an experimental file system [5][9]. Group 3: Arguments and Responses - Kent Overstreet defended his actions by arguing that user safety should take precedence over strict adherence to rules, highlighting the potential irreversible data loss that could occur if the file system fails [6]. - He pointed out that the journal_rewind patch was a small addition aimed at improving data recovery, and delaying its integration could significantly impact users [6]. Group 4: Community Reactions - The community has split into two camps: one supporting Linus Torvalds' adherence to process and the other backing Kent Overstreet's user-centric approach [10]. - Some developers criticized the rigid application of rules, suggesting that it could hinder the timely introduction of significant new features into the Linux kernel [11].

Core Viewpoint - Linus Torvalds criticizes the implementation of case-insensitive file systems, deeming it a fundamental error that should not have been pursued in the first place [5][6][7] Group 1: Background on Bcachefs - Bcachefs is a copy-on-write (COW) file system for Linux, developed by Kent Overstreet since 2015 [3] - A previous patch for case folding support was integrated into Bcachefs, but it failed to function correctly, prompting a new fix before the release of Linux 6.15-rc4 [3][4] - Overstreet acknowledged the oversight in testing and emphasized the importance of verifying code behavior personally rather than relying solely on automated tests [4] Group 2: Linus's Critique - Linus argues that the attempt to implement case insensitivity leads to more uncontrollable issues, particularly due to the complexities of the Unicode standard [6] - He highlights the potential security risks associated with case folding, using the example of similar-looking Unicode characters that could be misidentified as the same file [6][10] - Linus expresses frustration over the continued acceptance of case insensitivity in file systems, comparing it to a flawed design from older systems like FAT [5][6] Group 3: Developer Reactions - Some developers support Linus's stance, emphasizing the importance of case sensitivity in programming and the issues caused by case-insensitive systems [9] - Others argue against Linus's viewpoint, citing practical difficulties in managing files with case sensitivity in certain environments [9] - The debate reflects a broader discussion on the need for standardization and the implications of case sensitivity in file systems [8][10]