On Tue, Jan 30, 2024 at 09:51:59AM +0100, Kevin Wolf wrote:
> Am 29.01.2024 um 19:53 hat Richard W.M. Jones geschrieben:
> > With GCC 14 the code failed to compile on i686 (and was wrong for any
> > version of GCC):
> >
> > ../block/blkio.c: In function ‘blkio_file_open’:
> > ../block/blkio.c:857:28: error: passing argument 3 of ‘blkio_get_uint64’
> > from incompatible pointer type [-Wincompatible-pointer-types]
> > 857 | &s->mem_region_alignment);
> > | ^~~~~~~~~~~~~~~~~~~~~~~~
> > | |
> > | size_t * {aka unsigned int *}
> > In file included from ../block/blkio.c:12:
> > /usr/include/blkio.h:49:67: note: expected ‘uint64_t *’ {aka ‘long long
> > unsigned int *’} but argument is of type ‘size_t *’ {aka ‘unsigned int *’}
> > 49 | int blkio_get_uint64(struct blkio *b, const char *name, uint64_t
> > *value);
> > |
> > ~~~~~~~~~~^~~~~
> >
> > Signed-off-by: Richard W.M. Jones <rjo...@redhat.com>
>
> Why not simply make BDRVBlkioState.mem_region_alignment a uint64_t
> instead of keeping it size_t and doing an additional conversion with
> a check that requires an #if (probably to avoid a warning on 64 bit
> hosts because the condition is never true)?
The smaller change (attached) does work on i686, but this worries me a
little (although it doesn't give any error or warning):
if (((uintptr_t)host | size) % s->mem_region_alignment) {
error_setg(errp, "unaligned buf %p with size %zu", host, size);
return BMRR_FAIL;
}
Rich.
> Kevin
>
> > block/blkio.c | 12 +++++++++++-
> > 1 file changed, 11 insertions(+), 1 deletion(-)
> >
> > diff --git a/block/blkio.c b/block/blkio.c
> > index 0a0a6c0f5fd..52d78935147 100644
> > --- a/block/blkio.c
> > +++ b/block/blkio.c
> > @@ -794,6 +794,7 @@ static int blkio_file_open(BlockDriverState *bs, QDict
> > *options, int flags,
> > const char *blkio_driver = bs->drv->protocol_name;
> > BDRVBlkioState *s = bs->opaque;
> > int ret;
> > + uint64_t val;
> >
> > ret = blkio_create(blkio_driver, &s->blkio);
> > if (ret < 0) {
> > @@ -854,7 +855,7 @@ static int blkio_file_open(BlockDriverState *bs, QDict
> > *options, int flags,
> >
> > ret = blkio_get_uint64(s->blkio,
> > "mem-region-alignment",
> > - &s->mem_region_alignment);
> > + &val);
> > if (ret < 0) {
> > error_setg_errno(errp, -ret,
> > "failed to get mem-region-alignment: %s",
> > @@ -862,6 +863,15 @@ static int blkio_file_open(BlockDriverState *bs, QDict
> > *options, int flags,
> > blkio_destroy(&s->blkio);
> > return ret;
> > }
> > +#if HOST_LONG_BITS == 32
> > + if (val > SIZE_MAX) {
> > + error_setg_errno(errp, ERANGE,
> > + "mem-region-alignment too large for size_t");
> > + blkio_destroy(&s->blkio);
> > + return -ERANGE;
> > + }
> > +#endif
> > + s->mem_region_alignment = (size_t)val;
> >
> > ret = blkio_get_bool(s->blkio,
> > "may-pin-mem-regions",
> > --
> > 2.43.0
> >
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
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>From 500f3a81652dcefa79a4864c1f3fa6747c16952e Mon Sep 17 00:00:00 2001
From: "Richard W.M. Jones" <rjo...@redhat.com>
Date: Mon, 29 Jan 2024 18:20:46 +0000
Subject: [PATCH] block/blkio: Make s->mem_region_alignment be 64 bits
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
With GCC 14 the code failed to compile on i686 (and was wrong for any
version of GCC):
../block/blkio.c: In function ‘blkio_file_open’:
../block/blkio.c:857:28: error: passing argument 3 of ‘blkio_get_uint64’ from
incompatible pointer type [-Wincompatible-pointer-types]
857 | &s->mem_region_alignment);
| ^~~~~~~~~~~~~~~~~~~~~~~~
| |
| size_t * {aka unsigned int *}
In file included from ../block/blkio.c:12:
/usr/include/blkio.h:49:67: note: expected ‘uint64_t *’ {aka ‘long long
unsigned int *’} but argument is of type ‘size_t *’ {aka ‘unsigned int *’}
49 | int blkio_get_uint64(struct blkio *b, const char *name, uint64_t
*value);
| ~~~~~~~~~~^~~~~
Signed-off-by: Richard W.M. Jones <rjo...@redhat.com>
---
block/blkio.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/block/blkio.c b/block/blkio.c
index 0a0a6c0f5fd..bc2f21784c7 100644
--- a/block/blkio.c
+++ b/block/blkio.c
@@ -68,7 +68,7 @@ typedef struct {
CoQueue bounce_available;
/* The value of the "mem-region-alignment" property */
- size_t mem_region_alignment;
+ uint64_t mem_region_alignment;
/* Can we skip adding/deleting blkio_mem_regions? */
bool needs_mem_regions;
--
2.43.0
