IF YOU WOULD LIKE TO GET AN ACCOUNT, please write an
email to Administrator. User accounts are meant only to access repo
and report issues and/or generate pull requests.
This is a purpose-specific Git hosting for
BaseALT
projects. Thank you for your understanding!
Только зарегистрированные пользователи имеют доступ к сервису!
Для получения аккаунта, обратитесь к администратору.
This is a backport of a fix that was done in OpenSBI: ec0559eb315b
("lib: sbi_misaligned_ldst: Fix handling of C.SWSP and C.SDSP").
Unlike C.LWSP/C.LDSP, these encodings can be used with the zero
register, so checking that the rs2 field is non-zero is unnecessary.
Additionally, the previous check was incorrect since it was checking
the immediate field of the instruction instead of the rs2 field.
Fixes: 956d705dd279 ("riscv: Unaligned load/store handling for M_MODE")
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Link: https://lore.kernel.org/r/20231103090223.702340-1-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This function shouldn't be __init, since it's called during hotplug. The
warning says it well enough:
WARNING: modpost: vmlinux: section mismatch in reference:
check_unaligned_access_all_cpus+0x13a (section: .text) ->
unaligned_emulation_finish (section: .init.text)
Signed-off-by: Evan Green <evan@rivosinc.com>
Fixes: 71c54b3d169d ("riscv: report misaligned accesses emulation to hwprobe")
Link: https://lore.kernel.org/r/20231106231105.3141413-1-evan@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Now that trap support is ready to handle misalignment errors in S-mode,
allow the user to control the behavior of misaligned accesses using
prctl(PR_SET_UNALIGN). Add an align_ctl flag in thread_struct which
will be used to determine if we should SIGBUS the process or not on
such fault.
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Link: https://lore.kernel.org/r/20231004151405.521596-9-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
hwprobe provides a way to report if misaligned access are emulated. In
order to correctly populate that feature, we can check if it actually
traps when doing a misaligned access. This can be checked using an
exception table entry which will actually be used when a misaligned
access is done from kernel mode.
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Link: https://lore.kernel.org/r/20231004151405.521596-8-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This sysctl tuning option allows the user to disable misaligned access
handling globally on the system. This will also be used by misaligned
detection code to temporarily disable misaligned access handling.
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Link: https://lore.kernel.org/r/20231004151405.521596-6-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This support is partially based of openSBI misaligned emulation floating
point instruction support. It provides support for the existing
floating point instructions (both for 32/64 bits as well as compressed
ones). Since floating point registers are not part of the pt_regs
struct, we need to modify them directly using some assembly. We also
dirty the pt_regs status in case we modify them to be sure context
switch will save FP state. With this support, Linux is on par with
openSBI support.
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Link: https://lore.kernel.org/r/20231004151405.521596-5-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Misalignment trap handling is only supported for M-mode and uses direct
accesses to user memory. In S-mode, when handling usermode fault, this
requires to use the get_user()/put_user() accessors. Implement
load_u8(), store_u8() and get_insn() using these accessors for
userspace and direct text access for kernel.
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Björn Töpel <bjorn@rivosinc.com>
Link: https://lore.kernel.org/r/20231004151405.521596-3-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Replace macros by the only two function calls that are done from this
file, store_u8() and load_u8().
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Link: https://lore.kernel.org/r/20231004151405.521596-2-cleger@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Add handlers for unaligned load and store traps that may be generated
by applications. Code heavily inspired from the OpenSBI project.
Handling of the unaligned access traps is suitable for applications
compiled with or without compressed instructions and is independent of
the kernel CONFIG_RISCV_ISA_C option value.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
