>> + * Only do the expensive exception table search when we might be at >> + * risk of a deadlock: >> + * 1. We failed to acquire mmap_sem, and >> + * 2. The access was an explicit kernel-mode access >> + * (X86_PF_USER=0). > > Might be worth reminding the reader that X86_PF_USER will be set in > sw_error_code for implicit accesses. I saw "explicit" and my mind > immediately jumped to hw_error_code for whatever reason. E.g.: > > * 2. The access was an explicit kernel-mode access (we set X86_PF_USER > * in sw_error_code for implicit kernel-mode accesses).
Yeah, that was not worded well. Is this better? > * Only do the expensive exception table search when we might be at > * risk of a deadlock: > * 1. We failed to acquire mmap_sem, and > * 2. The access was an explicit kernel-mode access. An access > * from user-mode will X86_PF_USER=1 set via hw_error_code or > * set in sw_error_code if it were an implicit kernel-mode > * access that originated in user mode.
