From dd05add7b2b6004c5fa3a1f276f56d8668f86b65 Mon Sep 17 00:00:00 2001 From: Paulo Alcantara Date: Sat, 26 Sep 2026 19:20:30 -0300 Subject: netfs: zero the tail of a short DIO/unbuffered read The buffered read collector zero-fills the tail of a short read that stops below the inode's i_size (netfs_clear_unread()), so a read that races an extending write still returns the expected number of bytes. The non-buffered collector path does no such thing: it just records how much was transferred. Add the same zero-fill for the non-buffered case, gated on NETFS_SREQ_CLEAR_TAIL: a subreq's source sets that flag when a short result from it is known to be safe to treat as a hole, as opposed to NETFS_SREQ_HIT_EOF, which means the read genuinely ran off the end of the file and should be reported short as-is. Only CLEAR_TAIL should zero-fill here; a real EOF must stay a real short read. No source currently sets CLEAR_TAIL on an unbuffered/DIO subrequest, so this is inert on its own -- a following change teaches cifs to set it in the one case that needs it. Fixes: e2d46f2ec332 ("netfs: Change the read result collector to only use one work item") Reviewed-by: David Howells Reviewed-by: Namjae Jeon Signed-off-by: Paulo Alcantara Cc: Christian Brauner Cc: Matthew Wilcox Cc: Ronnie Sahlberg Cc: Shyam Prasad N Cc: Tom Talpey Cc: Bharath SM Cc: stable@vger.kernel.org --- scripts/subarch.include | 13 +++++++++++++ 1 file changed, 13 insertions(+) create mode 100644 scripts/subarch.include (limited to 'scripts/subarch.include') diff --git a/scripts/subarch.include b/scripts/subarch.include new file mode 100644 index 000000000..c4592d59d --- /dev/null +++ b/scripts/subarch.include @@ -0,0 +1,13 @@ +# SUBARCH tells the usermode build what the underlying arch is. That is set +# first, and if a usermode build is happening, the "ARCH=um" on the command +# line overrides the setting of ARCH below. If a native build is happening, +# then ARCH is assigned, getting whatever value it gets normally, and +# SUBARCH is subsequently ignored. + +SUBARCH := $(shell uname -m | sed -e s/i.86/x86/ -e s/x86_64/x86/ \ + -e s/sun4u/sparc64/ \ + -e /^arm64$$/!s/arm.*/arm/ -e s/sa110/arm/ \ + -e s/s390x/s390/ \ + -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \ + -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ \ + -e s/riscv.*/riscv/ -e s/loongarch.*/loongarch/) -- cgit v1.3.1