1. 16 Sep, 2022 2 commits
    • Mark Rutland's avatar
      arm64: die(): pass 'err' as long · 18906ff9
      Mark Rutland authored
      Recently, we reworked a lot of code to consistentlt pass ESR_ELx as a
      64-bit quantity. However, we missed that this can be passed into die()
      and __die() as the 'err' parameter where it is truncated to a 32-bit
      int.
      
      As notify_die() already takes 'err' as a long, this patch changes die()
      and __die() to also take 'err' as a long, ensuring that the full value
      of ESR_ELx is retained.
      
      At the same time, die() is updated to consistently log 'err' as a
      zero-padded 64-bit quantity.
      
      Subsequent patches will pass the ESR_ELx value to die() for a number of
      exceptions.
      Signed-off-by: default avatarMark Rutland <mark.rutland@arm.com>
      Reviewed-by: default avatarMark Brown <broonie@kernel.org>
      Reviewed-by: default avatarAnshuman Khandual <anshuman.khandual@arm.com>
      Cc: Alexandru Elisei <alexandru.elisei@arm.com>
      Cc: Amit Daniel Kachhap <amit.kachhap@arm.com>
      Cc: James Morse <james.morse@arm.com>
      Cc: Will Deacon <will@kernel.org>
      Link: https://lore.kernel.org/r/20220913101732.3925290-3-mark.rutland@arm.comSigned-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      18906ff9
    • Mark Rutland's avatar
      arm64: report EL1 UNDEFs better · b502c87d
      Mark Rutland authored
      If an UNDEFINED exception is taken from EL1, and do_undefinstr() doesn't
      find any suitable undef_hook, it will call:
      
      	BUG_ON(!user_mode(regs))
      
      ... and the kernel will report a failure witin do_undefinstr() rather
      than reporting the original context that the UNDEFINED exception was
      taken from. The pt_regs and ESR value reported within the BUG() handler
      will be from within do_undefinstr() and the code dump will be for the
      BRK in BUG_ON(), which isn't sufficient to debug the cause of the
      original exception.
      
      This patch makes the reporting better by having do_undefinstr() call
      die() directly in this case to report the original context from which
      the UNDEFINED exception was taken.
      
      Prior to this patch, an undefined instruction is reported as:
      
      | kernel BUG at arch/arm64/kernel/traps.c:497!
      | Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
      | Modules linked in:
      | CPU: 0 PID: 0 Comm: swapper Not tainted 5.19.0-rc3-00127-geff044f1b04e-dirty #3
      | Hardware name: linux,dummy-virt (DT)
      | pstate: 000000c5 (nzcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
      | pc : do_undefinstr+0x28c/0x2ac
      | lr : do_undefinstr+0x298/0x2ac
      | sp : ffff800009f63bc0
      | x29: ffff800009f63bc0 x28: ffff800009f73c00 x27: ffff800009644a70
      | x26: ffff8000096778a8 x25: 0000000000000040 x24: 0000000000000000
      | x23: 00000000800000c5 x22: ffff800009894060 x21: ffff800009f63d90
      | x20: 0000000000000000 x19: ffff800009f63c40 x18: 0000000000000006
      | x17: 0000000000403000 x16: 00000000bfbfd000 x15: ffff800009f63830
      | x14: ffffffffffffffff x13: 0000000000000000 x12: 0000000000000019
      | x11: 0101010101010101 x10: 0000000000161b98 x9 : 0000000000000000
      | x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
      | x5 : ffff800009f761d0 x4 : 0000000000000000 x3 : ffff80000a2b80f8
      | x2 : 0000000000000000 x1 : ffff800009f73c00 x0 : 00000000800000c5
      | Call trace:
      |  do_undefinstr+0x28c/0x2ac
      |  el1_undef+0x2c/0x4c
      |  el1h_64_sync_handler+0x84/0xd0
      |  el1h_64_sync+0x64/0x68
      |  setup_arch+0x550/0x598
      |  start_kernel+0x88/0x6ac
      |  __primary_switched+0xb8/0xc0
      | Code: 17ffff95 a9425bf5 17ffffb8 a9025bf5 (d4210000)
      
      With this patch applied, an undefined instruction is reported as:
      
      | Internal error: Oops - Undefined instruction: 0 [#1] PREEMPT SMP
      | Modules linked in:
      | CPU: 0 PID: 0 Comm: swapper Not tainted 5.19.0-rc3-00128-gf27cfcc80e52-dirty #5
      | Hardware name: linux,dummy-virt (DT)
      | pstate: 800000c5 (Nzcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
      | pc : setup_arch+0x550/0x598
      | lr : setup_arch+0x50c/0x598
      | sp : ffff800009f63d90
      | x29: ffff800009f63d90 x28: 0000000081000200 x27: ffff800009644a70
      | x26: ffff8000096778c8 x25: 0000000000000040 x24: 0000000000000000
      | x23: 0000000000000100 x22: ffff800009f69a58 x21: ffff80000a2b80b8
      | x20: 0000000000000000 x19: 0000000000000000 x18: 0000000000000006
      | x17: 0000000000403000 x16: 00000000bfbfd000 x15: ffff800009f63830
      | x14: ffffffffffffffff x13: 0000000000000000 x12: 0000000000000019
      | x11: 0101010101010101 x10: 0000000000161b98 x9 : 0000000000000000
      | x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
      | x5 : 0000000000000008 x4 : 0000000000000010 x3 : 0000000000000000
      | x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
      | Call trace:
      |  setup_arch+0x550/0x598
      |  start_kernel+0x88/0x6ac
      |  __primary_switched+0xb8/0xc0
      | Code: b4000080 90ffed80 912ac000 97db745f (00000000)
      Signed-off-by: default avatarMark Rutland <mark.rutland@arm.com>
      Reviewed-by: default avatarMark Brown <broonie@kernel.org>
      Cc: Alexandru Elisei <alexandru.elisei@arm.com>
      Cc: Amit Daniel Kachhap <amit.kachhap@arm.com>
      Cc: James Morse <james.morse@arm.com>
      Cc: Will Deacon <will@kernel.org>
      Reviewed-by: default avatarAnshuman Khandual <anshuman.khandual@arm.com>
      Link: https://lore.kernel.org/r/20220913101732.3925290-2-mark.rutland@arm.comSigned-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      b502c87d
  2. 28 Aug, 2022 25 commits
  3. 27 Aug, 2022 13 commits