commit d6a428fb583738ad685c91a684748cdee7b2a05f upstream. __clear_user() (and clear_user() which uses it), always access the user mode address space, which results in EVA store instructions when EVA is enabled even if the current user address limit is KERNEL_DS. Fix this by adding a new symbol __bzero_kernel for the normal kernel address space bzero in EVA mode, and call that from __clear_user() if eva_kernel_access(). Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Markos Chandras <markos.chandras@imgtec.com> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/10844/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org> [james.hogan@imgtec.com: backport] Signed-off-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
commit 51b1029d9966060c6ad02030e6f251425b4f06c1 upstream.
Commit cf62a8b8134dd3 ("MIPS: lib: memcpy: Use macro to build the
copy_user code") switched to a macro in order to build the memcpy
symbols in preparation for the EVA support. However, this commit
also removed the NOP instruction after the 'jr ra' when returning
back to the caller. This had no visible side-effects since the next
instruction was a load to the t0 register which was already in the
clobbered list, but it may have undesired effects in the future
if some other code is introduced in between the .Ldone and
the .Ll_exc_copy labels.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8512/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
This small update to the previous fix to __delay removes a conditional around the ABI-dependent subtraction operation within an inline asm in favor to the standard <asm/asm.h> LONG_SUBU macro. No change in code produced. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/6703/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Nobody is maintaining SMTC anymore and there also seems to be no userbase. Which is a pity - the SMTC technology primarily developed by Kevin D. Kissell <kevink@paralogos.com> is an ingenious demonstration for the MT ASE's power and elegance. Based on Markos Chandras <Markos.Chandras@imgtec.com> patch https://patchwork.linux-mips.org/patch/6719/ which while very similar did no longer apply cleanly when I tried to merge it plus some additional post-SMTC cleanup - SMTC was a feature as tricky to remove as it was to merge once upon a time. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This change reverts most of commit 60724ca59eda766a30be57aec6b49bc3e2bead91 [MIPS: IP checksums: Remove unncessary .set pseudos] that introduced warnings with the CPU_DADDI_WORKAROUNDS option set: arch/mips/lib/csum_partial.S: Assembler messages: arch/mips/lib/csum_partial.S:467: Warning: used $3 with ".set at=$3" arch/mips/lib/csum_partial.S:467: Warning: used $3 with ".set at=$3" arch/mips/lib/csum_partial.S:467: Warning: used $3 with ".set at=$3" arch/mips/lib/csum_partial.S:467: Warning: used $3 with ".set at=$3" arch/mips/lib/csum_partial.S:467: Warning: used $3 with ".set at=$3" arch/mips/lib/csum_partial.S:467: Warning: used $3 with ".set at=$3" arch/mips/lib/csum_partial.S:467: Warning: used $3 with ".set at=$3" arch/mips/lib/csum_partial.S:467: Warning: used $3 with ".set at=$3" arch/mips/lib/csum_partial.S:467: Warning: used $3 with ".set at=$3" arch/mips/lib/csum_partial.S:467: Warning: used $3 with ".set at=$3" [...] arch/mips/lib/csum_partial.S:577: Warning: used $3 with ".set at=$3" arch/mips/lib/csum_partial.S:577: Warning: used $3 with ".set at=$3" arch/mips/lib/csum_partial.S:577: Warning: used $3 with ".set at=$3" arch/mips/lib/csum_partial.S:601: Warning: used $3 with ".set at=$3" arch/mips/lib/csum_partial.S:601: Warning: used $3 with ".set at=$3" arch/mips/lib/csum_partial.S:601: Warning: used $3 with ".set at=$3" arch/mips/lib/csum_partial.S:601: Warning: used $3 with ".set at=$3" [and so on, and so on...] The warnings are benign and good code is produced regardless because no macros that'd use the assembler's temporary register are involved, however the `.set noat' directives removed by the commit referred are crucial to guarantee this is still going to be the case after any changes in the future. Therefore they need to be brought back to place which this change does. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/6686/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This corrects assembler warnings and broken code generated in __strncpy_from_user_asm: arch/mips/lib/strncpy_user.S: Assembler messages: arch/mips/lib/strncpy_user.S:52: Warning: Macro instruction expanded into multiple instructions in a branch delay slot with the CPU_DADDI_WORKAROUNDS option set. The function schedules delay slots manually where there is really no need to as GAS is happy to do it all itself, so undo it all and remove `.set noreorder'. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/6685/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
With CPU_DADDI_WORKAROUNDS enabled __delay assembles with a macro in a
branch delay slot:
{standard input}: Assembler messages:
{standard input}:18: Warning: Macro instruction expanded into multiple
instructions in a branch delay slot
and broken code results:
0000000000000000 <__delay>:
0: 1480ffff bnez a0,0 <__delay>
4: 24010001 li at,1
8: 0081202f dsubu a0,a0,at
c: 03e00008 jr ra
10: 00000000 nop
14: 00000000 nop
Consequently the function loops indefinitely, showing up prominently as a
hang in the delay loop calibration at bootstrap.
This change corrects the problem by forcing the immediate 1 into a
register while keeping code produced identical where CPU_DADDI_WORKAROUNDS
is disabled.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6669/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Use EVA specific functions to read and write data to user address space. Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
In preparation for EVA support, we use a macro to build the __csum_partial_copy_user main code so it can be shared across multiple implementations. EVA uses the same code but it replaces the load/store/prefetch instructions with the EVA specific ones therefore using a macro avoids unnecessary code duplications. Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Each load/store macro always adds an entry to the __ex_table using the EXC macro. There are cases where a load instruction may never fail such as when we are sure the load happens in the kernel address space. Therefore, we merge these the EXC and LOADX/STOREX macros into a single one. We also expand the argument list in the EXC macro to make the macro more flexible. The extra 'type' argument is not used by this commit, but it will be used when EVA support is added to memcpy. Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>