From: Sasha Levin <sashal@kernel.org>
To: Jason Gunthorpe <jgg@ziepe.ca>, Leon Romanovsky <leon@kernel.org>,
Andrew Morton <akpm@linux-foundation.org>,
David Hildenbrand <david@kernel.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>,
"Liam R. Howlett" <liam@infradead.org>,
Vlastimil Babka <vbabka@kernel.org>,
Mike Rapoport <rppt@kernel.org>,
Suren Baghdasaryan <surenb@google.com>,
Michal Hocko <mhocko@suse.com>, Shuah Khan <shuah@kernel.org>,
Peter Xu <peterx@redhat.com>,
linux-mm@kvack.org, linux-kselftest@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: [PATCH] selftests/mm: fix pointer width warnings on 32-bit architectures
Date: Tue, 3 Nov 2026 11:39:07 -0500 [thread overview]
Message-ID: <20261103163907.640667-1-sashal@kernel.org> (raw)
Several mm tests convert between pointers and 64-bit integers with a
plain cast, which warns on 32-bit architectures, and hugetlb-mremap
passes 47-bit mmap() hints that don't fit in an unsigned long:
uffd-unit-tests.c:344:31: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
Cast through uintptr_t where pointers meet the 64-bit UAPI fields and
the 64-bit address arithmetic in mremap_test, and include stdint.h there
for it. The hugetlb-mremap hints don't fit in a 32-bit address space, so
only pass them when long is 64 bits.
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
Found with 32-bit builds of the selftests (gcc 16 and clang 21 with
-m32, with and without -D_TIME_BITS=64 -D_FILE_OFFSET_BITS=64);
KernelCI's 32-bit arm builds show the same warnings. The changed files
build without them now, and the x86_64 builds don't change.
tools/testing/selftests/mm/hmm-tests.c | 4 +-
tools/testing/selftests/mm/hugetlb-mremap.c | 17 ++++---
tools/testing/selftests/mm/migration.c | 4 +-
tools/testing/selftests/mm/mremap_test.c | 13 +++---
tools/testing/selftests/mm/uffd-common.c | 2 +-
tools/testing/selftests/mm/uffd-unit-tests.c | 48 ++++++++++----------
6 files changed, 47 insertions(+), 41 deletions(-)
diff --git a/tools/testing/selftests/mm/hmm-tests.c b/tools/testing/selftests/mm/hmm-tests.c
index e5f273ca84c10..2a8806a131a5b 100644
--- a/tools/testing/selftests/mm/hmm-tests.c
+++ b/tools/testing/selftests/mm/hmm-tests.c
@@ -196,8 +196,8 @@ static int hmm_dmirror_cmd(int fd,
int ret;
/* Simulate a device reading system memory. */
- cmd.addr = (__u64)buffer->ptr;
- cmd.ptr = (__u64)buffer->mirror;
+ cmd.addr = (__u64)(uintptr_t)buffer->ptr;
+ cmd.ptr = (__u64)(uintptr_t)buffer->mirror;
cmd.npages = npages;
for (;;) {
diff --git a/tools/testing/selftests/mm/hugetlb-mremap.c b/tools/testing/selftests/mm/hugetlb-mremap.c
index 9b724af66e938..531f270fabfb5 100644
--- a/tools/testing/selftests/mm/hugetlb-mremap.c
+++ b/tools/testing/selftests/mm/hugetlb-mremap.c
@@ -33,6 +33,11 @@
#define PROTECTION (PROT_READ | PROT_WRITE | PROT_EXEC)
#define FLAGS (MAP_HUGETLB | MAP_SHARED)
+static void *addr_hint(unsigned long long addr)
+{
+ return sizeof(long) == 8 ? (void *)(uintptr_t)addr : NULL;
+}
+
static void check_bytes(char *addr)
{
ksft_print_msg("First hex is %x\n", *((unsigned int *)addr));
@@ -130,21 +135,21 @@ int main(int argc, char *argv[])
ksft_exit_fail_msg("Open failed: %s\n", strerror(errno));
/* mmap to a PUD aligned address to hopefully trigger pmd sharing. */
- unsigned long suggested_addr = 0x7eaa40000000;
- void *haddr = mmap((void *)suggested_addr, length, PROTECTION, FLAGS, fd, 0);
+ void *haddr = mmap(addr_hint(0x7eaa40000000ULL), length, PROTECTION, FLAGS,
+ fd, 0);
ksft_print_msg("Map haddr: Returned address is %p\n", haddr);
if (haddr == MAP_FAILED)
ksft_exit_fail_msg("mmap1: %s\n", strerror(errno));
/* mmap again to a dummy address to hopefully trigger pmd sharing. */
- suggested_addr = 0x7daa40000000;
- void *daddr = mmap((void *)suggested_addr, length, PROTECTION, FLAGS, fd, 0);
+ void *daddr = mmap(addr_hint(0x7daa40000000ULL), length, PROTECTION, FLAGS,
+ fd, 0);
ksft_print_msg("Map daddr: Returned address is %p\n", daddr);
if (daddr == MAP_FAILED)
ksft_exit_fail_msg("mmap3: %s\n", strerror(errno));
- suggested_addr = 0x7faa40000000;
- void *vaddr = mmap((void *)suggested_addr, length, PROTECTION, FLAGS, fd, 0);
+ void *vaddr = mmap(addr_hint(0x7faa40000000ULL), length, PROTECTION, FLAGS,
+ fd, 0);
ksft_print_msg("Map vaddr: Returned address is %p\n", vaddr);
if (vaddr == MAP_FAILED)
ksft_exit_fail_msg("mmap2: %s\n", strerror(errno));
diff --git a/tools/testing/selftests/mm/migration.c b/tools/testing/selftests/mm/migration.c
index d1d0989ed2cad..1c5208ce048ee 100644
--- a/tools/testing/selftests/mm/migration.c
+++ b/tools/testing/selftests/mm/migration.c
@@ -236,7 +236,7 @@ TEST_F_TIMEOUT(migration, private_anon_thp, 2*RUNTIME)
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
ASSERT_NE(ptr, MAP_FAILED);
- ptr = (uint64_t *) ALIGN((uintptr_t) ptr, pmdsize);
+ ptr = (uint64_t *)(uintptr_t)ALIGN((uintptr_t) ptr, pmdsize);
ASSERT_EQ(madvise(ptr, pmdsize, MADV_HUGEPAGE), 0);
memset(ptr, 0xde, pmdsize);
for (i = 0; i < self->nthreads; i++)
@@ -270,7 +270,7 @@ TEST_F_TIMEOUT(migration, shared_anon_thp, 2*RUNTIME)
MAP_SHARED | MAP_ANONYMOUS, -1, 0);
ASSERT_NE(ptr, MAP_FAILED);
- ptr = (uint64_t *) ALIGN((uintptr_t) ptr, pmdsize);
+ ptr = (uint64_t *)(uintptr_t)ALIGN((uintptr_t) ptr, pmdsize);
ASSERT_EQ(madvise(ptr, pmdsize, MADV_HUGEPAGE), 0);
memset(ptr, 0xde, pmdsize);
diff --git a/tools/testing/selftests/mm/mremap_test.c b/tools/testing/selftests/mm/mremap_test.c
index 31b484517bda6..7e7ca67f7e94c 100644
--- a/tools/testing/selftests/mm/mremap_test.c
+++ b/tools/testing/selftests/mm/mremap_test.c
@@ -15,6 +15,7 @@
#include <syscall.h>
#include <time.h>
#include <stdbool.h>
+#include <stdint.h>
#include "kselftest.h"
@@ -190,7 +191,7 @@ static void *get_source_mapping(struct config c)
if (addr < mmap_min_addr)
goto retry;
- src_addr = mmap((void *) addr, c.region_size, PROT_READ | PROT_WRITE,
+ src_addr = mmap((void *)(uintptr_t)addr, c.region_size, PROT_READ | PROT_WRITE,
MAP_FIXED_NOREPLACE | MAP_ANONYMOUS | MAP_SHARED,
-1, 0);
if (src_addr == MAP_FAILED) {
@@ -206,8 +207,8 @@ static void *get_source_mapping(struct config c)
* requested alignment of 2MB. This is done to reduce coincidental
* alignment in the tests.
*/
- if (((unsigned long long) src_addr & (c.src_alignment - 1)) ||
- !((unsigned long long) src_addr & c.src_alignment)) {
+ if (((unsigned long long)(uintptr_t)src_addr & (c.src_alignment - 1)) ||
+ !((unsigned long long)(uintptr_t)src_addr & c.src_alignment)) {
munmap(src_addr, c.region_size);
goto retry;
}
@@ -996,15 +997,15 @@ static long long remap_region(struct config c, unsigned int threshold_mb,
align_mask = ~(c.dest_alignment - 1);
/* Offset of destination address from the end of the source region */
offset = (c.overlapping) ? -c.dest_alignment : c.dest_alignment;
- addr = (void *) (((unsigned long long) src_addr + c.region_size
+ addr = (void *)(uintptr_t)(((unsigned long long)(uintptr_t)src_addr + c.region_size
+ offset) & align_mask);
/* Remap after the destination block preamble. */
addr += c.dest_preamble_size;
/* See comment in get_source_mapping() */
- if (!((unsigned long long) addr & c.dest_alignment))
- addr = (void *) ((unsigned long long) addr | c.dest_alignment);
+ if (!((unsigned long long)(uintptr_t)addr & c.dest_alignment))
+ addr = (void *)(uintptr_t)((unsigned long long)(uintptr_t)addr | c.dest_alignment);
/* Don't destroy existing mappings unless expected to overlap. */
while (!is_remap_region_valid(addr - c.dest_preamble_size,
diff --git a/tools/testing/selftests/mm/uffd-common.c b/tools/testing/selftests/mm/uffd-common.c
index a76851aced4d0..4188991fab245 100644
--- a/tools/testing/selftests/mm/uffd-common.c
+++ b/tools/testing/selftests/mm/uffd-common.c
@@ -488,7 +488,7 @@ void uffd_handle_page_fault(uffd_global_test_opts_t *gopts, struct uffd_msg *msg
*/
area = (uint8_t *)(gopts->area_dst +
- ((char *)msg->arg.pagefault.address -
+ ((char *)(uintptr_t)msg->arg.pagefault.address -
gopts->area_dst_alias));
for (b = 0; b < gopts->page_size; ++b)
area[b] = ~area[b];
diff --git a/tools/testing/selftests/mm/uffd-unit-tests.c b/tools/testing/selftests/mm/uffd-unit-tests.c
index 2a97ba1d6feb1..2e4d1742f340b 100644
--- a/tools/testing/selftests/mm/uffd-unit-tests.c
+++ b/tools/testing/selftests/mm/uffd-unit-tests.c
@@ -341,17 +341,17 @@ static void uffd_wp_unpopulated_test(uffd_global_test_opts_t *gopts, uffd_test_a
pagemap_fd = pagemap_open();
/* Test applying pte marker to anon unpopulated */
- wp_range(gopts->uffd, (uint64_t)gopts->area_dst, gopts->page_size, true);
+ wp_range(gopts->uffd, (uint64_t)(uintptr_t)gopts->area_dst, gopts->page_size, true);
value = pagemap_get_entry(pagemap_fd, gopts->area_dst);
pagemap_check_wp(value, true);
/* Test unprotect on anon pte marker */
- wp_range(gopts->uffd, (uint64_t)gopts->area_dst, gopts->page_size, false);
+ wp_range(gopts->uffd, (uint64_t)(uintptr_t)gopts->area_dst, gopts->page_size, false);
value = pagemap_get_entry(pagemap_fd, gopts->area_dst);
pagemap_check_wp(value, false);
/* Test zap on anon marker */
- wp_range(gopts->uffd, (uint64_t)gopts->area_dst, gopts->page_size, true);
+ wp_range(gopts->uffd, (uint64_t)(uintptr_t)gopts->area_dst, gopts->page_size, true);
if (madvise(gopts->area_dst, gopts->page_size, MADV_DONTNEED))
err("madvise(MADV_DONTNEED) failed");
value = pagemap_get_entry(pagemap_fd, gopts->area_dst);
@@ -366,7 +366,7 @@ static void uffd_wp_unpopulated_test(uffd_global_test_opts_t *gopts, uffd_test_a
err("madvise(MADV_DONTNEED) failed");
/* Test read-zero-page upon pte marker */
- wp_range(gopts->uffd, (uint64_t)gopts->area_dst, gopts->page_size, true);
+ wp_range(gopts->uffd, (uint64_t)(uintptr_t)gopts->area_dst, gopts->page_size, true);
*(volatile char *)gopts->area_dst;
/* Drop it to make pte none again */
if (madvise(gopts->area_dst, gopts->page_size, MADV_DONTNEED))
@@ -389,7 +389,7 @@ static void uffd_wp_fork_test_common(uffd_global_test_opts_t *gopts, uffd_test_a
/* Touch the page */
*gopts->area_dst = 1;
- wp_range(gopts->uffd, (uint64_t)gopts->area_dst, gopts->page_size, true);
+ wp_range(gopts->uffd, (uint64_t)(uintptr_t)gopts->area_dst, gopts->page_size, true);
value = pagemap_get_entry(pagemap_fd, gopts->area_dst);
pagemap_check_wp(value, true);
if (pagemap_test_fork(gopts, with_event, false)) {
@@ -430,7 +430,7 @@ static void uffd_wp_fork_test_common(uffd_global_test_opts_t *gopts, uffd_test_a
}
/* Unprotect; this tests swap pte modifications */
- wp_range(gopts->uffd, (uint64_t)gopts->area_dst, gopts->page_size, false);
+ wp_range(gopts->uffd, (uint64_t)(uintptr_t)gopts->area_dst, gopts->page_size, false);
value = pagemap_get_entry(pagemap_fd, gopts->area_dst);
pagemap_check_wp(value, false);
@@ -469,7 +469,7 @@ static void uffd_wp_fork_pin_test_common(uffd_global_test_opts_t *gopts,
/* Touch the page */
*gopts->area_dst = 1;
- wp_range(gopts->uffd, (uint64_t)gopts->area_dst, gopts->page_size, true);
+ wp_range(gopts->uffd, (uint64_t)(uintptr_t)gopts->area_dst, gopts->page_size, true);
/*
* 1. First pin, then fork(). This tests fork() special path when
@@ -675,7 +675,7 @@ static void uffd_rwp_async_test(uffd_global_test_opts_t *gopts,
err("register failure");
/* RW-protect all pages (sets protnone) */
- rwprotect_range(gopts->uffd, (uint64_t)gopts->area_dst,
+ rwprotect_range(gopts->uffd, (uint64_t)(uintptr_t)gopts->area_dst,
nr_pages * page_size, true);
/* Access all pages — should auto-resolve, no faults */
@@ -739,7 +739,7 @@ static void uffd_rwp_sync_test(uffd_global_test_opts_t *gopts,
err("register failure");
/* RW-protect all pages */
- rwprotect_range(gopts->uffd, (uint64_t)gopts->area_dst,
+ rwprotect_range(gopts->uffd, (uint64_t)(uintptr_t)gopts->area_dst,
nr_pages * page_size, true);
/* Start fault handler thread */
@@ -816,7 +816,7 @@ static void uffd_rwp_pagemap_test(uffd_global_test_opts_t *gopts,
nr_pages * page_size))
err("register failure");
- rwprotect_range(gopts->uffd, (uint64_t)gopts->area_dst,
+ rwprotect_range(gopts->uffd, (uint64_t)(uintptr_t)gopts->area_dst,
nr_pages * page_size, true);
/* Touch first half of pages to re-activate them (async auto-resolve) */
@@ -825,7 +825,7 @@ static void uffd_rwp_pagemap_test(uffd_global_test_opts_t *gopts,
(void)*page;
}
- uint64_t start = (uint64_t)gopts->area_dst;
+ uint64_t start = (uint64_t)(uintptr_t)gopts->area_dst;
uint64_t boundary = start + (nr_pages / 2) * page_size;
uint64_t end = start + nr_pages * page_size;
@@ -844,7 +844,7 @@ static void uffd_rwp_pagemap_test(uffd_global_test_opts_t *gopts,
pm_arg.size = sizeof(pm_arg);
pm_arg.start = start;
pm_arg.end = end;
- pm_arg.vec = (uint64_t)regions;
+ pm_arg.vec = (uint64_t)(uintptr_t)regions;
pm_arg.vec_len = ARRAY_SIZE(regions);
pm_arg.category_mask = PAGE_IS_ACCESSED;
pm_arg.return_mask = PAGE_IS_ACCESSED;
@@ -897,7 +897,7 @@ static void uffd_rwp_mprotect_test(uffd_global_test_opts_t *gopts,
if (uffd_register_rwp(gopts->uffd, gopts->area_dst,
nr_pages * page_size))
err("register failure");
- rwprotect_range(gopts->uffd, (uint64_t)gopts->area_dst,
+ rwprotect_range(gopts->uffd, (uint64_t)(uintptr_t)gopts->area_dst,
nr_pages * page_size, true);
/* Round-trip mprotect(): PROT_NONE -> PROT_READ|PROT_WRITE */
@@ -937,9 +937,9 @@ static void uffd_rwp_mprotect_test(uffd_global_test_opts_t *gopts,
memset(&pm_arg, 0, sizeof(pm_arg));
pm_arg.size = sizeof(pm_arg);
- pm_arg.start = (uint64_t)gopts->area_dst;
- pm_arg.end = (uint64_t)gopts->area_dst + nr_pages * page_size;
- pm_arg.vec = (uint64_t)regions;
+ pm_arg.start = (uint64_t)(uintptr_t)gopts->area_dst;
+ pm_arg.end = (uint64_t)(uintptr_t)gopts->area_dst + nr_pages * page_size;
+ pm_arg.vec = (uint64_t)(uintptr_t)regions;
pm_arg.vec_len = ARRAY_SIZE(regions);
pm_arg.category_mask = PAGE_IS_ACCESSED;
pm_arg.category_inverted = PAGE_IS_ACCESSED;
@@ -982,7 +982,7 @@ static void uffd_rwp_gup_test(uffd_global_test_opts_t *gopts,
if (uffd_register_rwp(gopts->uffd, gopts->area_dst, gopts->page_size))
err("register failure");
- rwprotect_range(gopts->uffd, (uint64_t)gopts->area_dst,
+ rwprotect_range(gopts->uffd, (uint64_t)(uintptr_t)gopts->area_dst,
gopts->page_size, true);
if (pipe(pipefd))
@@ -1045,7 +1045,7 @@ static void uffd_rwp_async_toggle_test(uffd_global_test_opts_t *gopts,
err("register failure");
/* Phase 1: async detection — RW-protect, access first half */
- rwprotect_range(gopts->uffd, (uint64_t)gopts->area_dst,
+ rwprotect_range(gopts->uffd, (uint64_t)(uintptr_t)gopts->area_dst,
nr_pages * page_size, true);
for (p = 0; p < nr_pages / 2; p++) {
@@ -1092,7 +1092,7 @@ static void uffd_rwp_async_toggle_test(uffd_global_test_opts_t *gopts,
set_async_mode(gopts->uffd, true);
/* RW-protect and access again — should auto-resolve */
- rwprotect_range(gopts->uffd, (uint64_t)gopts->area_dst,
+ rwprotect_range(gopts->uffd, (uint64_t)(uintptr_t)gopts->area_dst,
nr_pages * page_size, true);
for (p = 0; p < nr_pages; p++) {
@@ -1127,7 +1127,7 @@ static void uffd_rwp_close_test(uffd_global_test_opts_t *gopts,
nr_pages * page_size))
err("register failure");
- rwprotect_range(gopts->uffd, (uint64_t)gopts->area_dst,
+ rwprotect_range(gopts->uffd, (uint64_t)(uintptr_t)gopts->area_dst,
nr_pages * page_size, true);
/* Close uffd — should restore protnone PTEs */
@@ -1169,7 +1169,7 @@ static void uffd_rwp_fork_test(uffd_global_test_opts_t *gopts,
/* Populate + RWP-protect */
*gopts->area_dst = 1;
- rwprotect_range(gopts->uffd, (uint64_t)gopts->area_dst,
+ rwprotect_range(gopts->uffd, (uint64_t)(uintptr_t)gopts->area_dst,
page_size, true);
/* Parent: verify uffd-wp bit is set before fork */
@@ -1223,7 +1223,7 @@ static void uffd_rwp_fork_pin_test(uffd_global_test_opts_t *gopts,
}
/* RWP-protect: PTE is now PAGE_NONE + uffd bit. */
- rwprotect_range(gopts->uffd, (uint64_t)gopts->area_dst, page_size, true);
+ rwprotect_range(gopts->uffd, (uint64_t)(uintptr_t)gopts->area_dst, page_size, true);
pagemap_fd = pagemap_open();
value = pagemap_get_entry(pagemap_fd, gopts->area_dst);
@@ -1332,7 +1332,7 @@ static void uffd_rwp_swap_cow_test(uffd_global_test_opts_t *gopts,
*gopts->area_dst = 0x11;
/* RWP-protect: PTE becomes PAGE_NONE + uffd bit (still exclusive). */
- rwprotect_range(gopts->uffd, (uint64_t)gopts->area_dst, page_size, true);
+ rwprotect_range(gopts->uffd, (uint64_t)(uintptr_t)gopts->area_dst, page_size, true);
/*
* Swap the page out while it is still exclusive: a shared (forked)
@@ -1498,7 +1498,7 @@ static int faulting_process(uffd_global_test_opts_t *gopts, int signal_test, boo
/* This is a WP request */
assert(steps == 2);
wp_range(gopts->uffd,
- (__u64)gopts->area_dst +
+ (__u64)(uintptr_t)gopts->area_dst +
offset,
gopts->page_size, false);
}
--
2.53.0
next reply other threads:[~2026-11-03 16:39 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-11-03 16:39 Sasha Levin [this message]
2026-11-03 17:13 ` Lorenzo Stoakes (ARM)
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