kernel/linux.git/arch/sparc/lib, branch v6.12.80

sparc: fix accurate exception reporting in copy_{from,to}_user for M7

2025-10-15T10:00:14+00:00

[ Upstream commit 936fb512752af349fc30ccbe0afe14a2ae6d7159 ] The referenced commit introduced exception handlers on user-space memory references in copy_from_user and copy_to_user. These handlers return from the respective function and calculate the remaining bytes left to copy using the current register contents. This commit fixes a couple of bad calculations. This will fix the return value of copy_from_user and copy_to_user in the faulting case. The behaviour of memcpy stays unchanged. Fixes: 34060b8fffa7 ("arch/sparc: Add accurate exception reporting in M7memcpy") Tested-by: John Paul Adrian Glaubitz # on Oracle SPARC S7 Tested-by: Tony Rodriguez # S7, see https://lore.kernel.org/r/98564e2e68df2dda0e00c67a75c7f7dfedb33c7e.camel@physik.fu-berlin.de Signed-off-by: Michael Karcher Reviewed-by: Andreas Larsson Link: https://lore.kernel.org/r/20250905-memcpy_series-v4-5-1ca72dda195b@mkarcher.dialup.fu-berlin.de Signed-off-by: Andreas Larsson Signed-off-by: Sasha Levin

sparc: fix accurate exception reporting in copy_to_user for Niagara 4

2025-10-15T10:00:14+00:00

[ Upstream commit 5a746c1a2c7980de6c888b6373299f751ad7790b ] The referenced commit introduced exception handlers on user-space memory references in copy_from_user and copy_to_user. These handlers return from the respective function and calculate the remaining bytes left to copy using the current register contents. This commit fixes a bad calculation. This will fix the return value of copy_to_user in a specific faulting case. The behaviour of memcpy stays unchanged. Fixes: 957077048009 ("sparc64: Convert NG4copy_{from,to}_user to accurate exception reporting.") Tested-by: John Paul Adrian Glaubitz # on Oracle SPARC T4-1 Signed-off-by: Michael Karcher Reviewed-by: Andreas Larsson Link: https://lore.kernel.org/r/20250905-memcpy_series-v4-4-1ca72dda195b@mkarcher.dialup.fu-berlin.de Signed-off-by: Andreas Larsson Signed-off-by: Sasha Levin

sparc: fix accurate exception reporting in copy_{from_to}_user for Niagara

2025-10-15T10:00:14+00:00

[ Upstream commit 0b67c8fc10b13a9090340c5f8a37d308f4e1571c ] The referenced commit introduced exception handlers on user-space memory references in copy_from_user and copy_to_user. These handlers return from the respective function and calculate the remaining bytes left to copy using the current register contents. This commit fixes a couple of bad calculations and a broken epilogue in the exception handlers. This will prevent crashes and ensure correct return values of copy_from_user and copy_to_user in the faulting case. The behaviour of memcpy stays unchanged. Fixes: 7ae3aaf53f16 ("sparc64: Convert NGcopy_{from,to}_user to accurate exception reporting.") Tested-by: John Paul Adrian Glaubitz # on SPARC T4 with modified kernel to use Niagara 1 code Tested-by: Magnus Lindholm # on Sun Fire T2000 Signed-off-by: Michael Karcher Tested-by: Ethan Hawke # on Sun Fire T2000 Tested-by: Ken Link # on Sun Fire T1000 Reviewed-by: Andreas Larsson Link: https://lore.kernel.org/r/20250905-memcpy_series-v4-3-1ca72dda195b@mkarcher.dialup.fu-berlin.de Signed-off-by: Andreas Larsson Signed-off-by: Sasha Levin

sparc: fix accurate exception reporting in copy_{from_to}_user for UltraSPARC III

2025-10-15T10:00:14+00:00

[ Upstream commit 47b49c06eb62504075f0f2e2227aee2e2c2a58b3 ] Anthony Yznaga tracked down that a BUG_ON in ext4 code with large folios enabled resulted from copy_from_user() returning impossibly large values greater than the size to be copied. This lead to __copy_from_iter() returning impossible values instead of the actual number of bytes it was able to copy. The BUG_ON has been reported in https://lore.kernel.org/r/b14f55642207e63e907965e209f6323a0df6dcee.camel@physik.fu-berlin.de The referenced commit introduced exception handlers on user-space memory references in copy_from_user and copy_to_user. These handlers return from the respective function and calculate the remaining bytes left to copy using the current register contents. The exception handlers expect that %o2 has already been masked during the bulk copy loop, but the masking was performed after that loop. This will fix the return value of copy_from_user and copy_to_user in the faulting case. The behaviour of memcpy stays unchanged. Fixes: ee841d0aff64 ("sparc64: Convert U3copy_{from,to}_user to accurate exception reporting.") Tested-by: John Paul Adrian Glaubitz # on Sun Netra 240 Reviewed-by: Anthony Yznaga Tested-by: René Rebe # on UltraSparc III+ and UltraSparc IIIi Signed-off-by: Michael Karcher Reviewed-by: Andreas Larsson Link: https://lore.kernel.org/r/20250905-memcpy_series-v4-2-1ca72dda195b@mkarcher.dialup.fu-berlin.de Signed-off-by: Andreas Larsson Signed-off-by: Sasha Levin

sparc: fix accurate exception reporting in copy_{from_to}_user for UltraSPARC

2025-10-15T10:00:14+00:00

[ Upstream commit 4fba1713001195e59cfc001ff1f2837dab877efb ] The referenced commit introduced exception handlers on user-space memory references in copy_from_user and copy_to_user. These handlers return from the respective function and calculate the remaining bytes left to copy using the current register contents. This commit fixes a couple of bad calculations. This will fix the return value of copy_from_user and copy_to_user in the faulting case. The behaviour of memcpy stays unchanged. Fixes: cb736fdbb208 ("sparc64: Convert U1copy_{from,to}_user to accurate exception reporting.") Tested-by: John Paul Adrian Glaubitz # on QEMU 10.0.3 Tested-by: René Rebe # on Ultra 5 UltraSparc IIi Tested-by: Jonathan 'theJPster' Pallant # on Sun Netra T1 Signed-off-by: Michael Karcher Reviewed-by: Andreas Larsson Link: https://lore.kernel.org/r/20250905-memcpy_series-v4-1-1ca72dda195b@mkarcher.dialup.fu-berlin.de Signed-off-by: Andreas Larsson Signed-off-by: Sasha Levin

sparc32: add __cmpxchg_u{8,16}() and teach __cmpxchg() to handle those sizes

2024-04-10T05:06:00+00:00

trivial now Signed-off-by: Al Viro Signed-off-by: Paul E. McKenney

sparc32: unify __cmpxchg_u{32,64}

2024-04-10T05:06:00+00:00

Add a macro that expands to one of those when given u32 or u64 as an argument - atomic32.c has a lot of similar stuff already. Signed-off-by: Al Viro Signed-off-by: Paul E. McKenney

sparc32: make the first argument of __cmpxchg_u64() volatile u64 *

2024-04-10T05:06:00+00:00

... to match all cmpxchg variants. Signed-off-by: Al Viro Signed-off-by: Paul E. McKenney

sparc32: make __cmpxchg_u32() return u32

2024-04-10T05:06:00+00:00

Conversion between u32 and unsigned long is tautological there, and the only use of return value is to return it from __cmpxchg() (which return unsigned long). Get rid of explicit casts in __cmpxchg_u32() call, while we are at it - normal conversions for arguments will do just fine. Signed-off-by: Al Viro Signed-off-by: Paul E. McKenney

sparc32: Use generic cmpdi2/ucmpdi2 variants

2024-03-08T20:20:23+00:00

Use the generic variants - the implementation is the same. As a nice side-effect fix the following warnings: cmpdi2.c: warning: no previous prototype for '__cmpdi2' [-Wmissing-prototypes] ucmpdi2.c: warning: no previous prototype for '__ucmpdi2' [-Wmissing-prototypes] Signed-off-by: Sam Ravnborg Fixes: 0fcb70851fbf ("Makefile.extrawarn: turn on missing-prototypes globally") Reviewed-by: Randy Dunlap Tested-by: Randy Dunlap # build-tested Reviewed-by: Maciej W. Rozycki Tested-by: Maciej W. Rozycki # build-tested Cc: "David S. Miller" Cc: Andreas Larsson Reviewed-by: Andreas Larsson Tested-by: Andreas Larsson Signed-off-by: Andreas Larsson Link: https://lore.kernel.org/r/20240224-sam-fix-sparc32-all-builds-v2-1-1f186603c5c4@ravnborg.org