On 9/17/24 6:56 AM, Shuah Khan wrote: > On 9/16/24 00:32, Muhammad Usama Anjum wrote: >> On 9/12/24 8:44 PM, Shuah Khan wrote: >>> On 9/12/24 04:31, Muhammad Usama Anjum wrote: >>>> The value of __NR_userfaultfd was changed to 282 when >>>> asm-generic/unistd.h was included. It makes the test to fail every time >>>> as the correct number of this syscall on x86_64 is 323. Fix the header >>>> to asm/unistd.h. >>>> >>> >>> "please elaborate every time" - I just built on my x86_64 and built >>> just fine. >> The build isn't broken. >> >>> I am not saying this isn't a problem, it is good to >>> understand why and how it is failing before making the change. >> I mean to say that the test is failing at run time because the correct >> userfaultfd syscall isn't being found with __NR_userfaultfd = 282. >> _NR_userfaultfd's value depends on the header. When asm-generic/unistd.h >> is included, its value (282) is wrong. I've tested on x86_64. >> > > Okay - how do you know this is wrong? can you provide more details. > > git grep _NR_userfaultfd > include/uapi/asm-generic/unistd.h:#define __NR_userfaultfd 282 > include/uapi/asm-generic/unistd.h:__SYSCALL(__NR_userfaultfd, > sys_userfaultfd) > tools/include/uapi/asm-generic/unistd.h:#define __NR_userfaultfd 282 > >> The fix is simple. Add the correct header which has _NR_userfaultfd = >> 323. grep -rnIF "#define __NR_userfaultfd" tools/include/uapi/asm-generic/unistd.h:681:#define __NR_userfaultfd 282 arch/x86/include/generated/uapi/asm/unistd_32.h:374:#define __NR_userfaultfd 374 arch/x86/include/generated/uapi/asm/unistd_64.h:327:#define __NR_userfaultfd 323 arch/x86/include/generated/uapi/asm/unistd_x32.h:282:#define __NR_userfaultfd (__X32_SYSCALL_BIT + 323) arch/arm/include/generated/uapi/asm/unistd-eabi.h:347:#define __NR_userfaultfd (__NR_SYSCALL_BASE + 388) arch/arm/include/generated/uapi/asm/unistd-oabi.h:359:#define __NR_userfaultfd (__NR_SYSCALL_BASE + 388) include/uapi/asm-generic/unistd.h:681:#define __NR_userfaultfd 282 The number is dependent on the architecture. The above data shows that: x86 374 x86_64 323 I'm unable to find the history of why it is set to 282 in unistd.h and when this problem happened. > > I need more details on this number. > > thanks, > -- Shuah -- BR, Muhammad Usama Anjum
