Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon:
"Two arm64 fixes for -rc6. They resolve a kernel NULL dereference in
kexec and bogus kernel page table dumping when userspace is configured
for 52-bit virtual addressing.
Summary:
- Fix kernel oops when attemping kexec_file() with a NULL cmdline
- Fix page table output in debugfs when ARM64_USER_VA_BITS_52=y"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: kexec_file: handle empty command-line
arm64: ptdump: Don't iterate kernel page tables using PTRS_PER_PXX
+32
-31
+3
-1
arch/arm64/kernel/machine_kexec_file.c
+3
-1
arch/arm64/kernel/machine_kexec_file.c
···
120
120
{
121
121
void *buf;
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size_t buf_size;
123
+
size_t cmdline_len;
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int ret;
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+
cmdline_len = cmdline ? strlen(cmdline) : 0;
125
127
buf_size = fdt_totalsize(initial_boot_params)
126
-
+ strlen(cmdline) + DTB_EXTRA_SPACE;
128
+
+ cmdline_len + DTB_EXTRA_SPACE;
127
129
128
130
for (;;) {
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buf = vmalloc(buf_size);
+29
-30
arch/arm64/mm/dump.c
+29
-30
arch/arm64/mm/dump.c
···
286
286
287
287
}
288
288
289
-
static void walk_pte(struct pg_state *st, pmd_t *pmdp, unsigned long start)
289
+
static void walk_pte(struct pg_state *st, pmd_t *pmdp, unsigned long start,
290
+
unsigned long end)
290
291
{
291
-
pte_t *ptep = pte_offset_kernel(pmdp, 0UL);
292
-
unsigned long addr;
293
-
unsigned i;
292
+
unsigned long addr = start;
293
+
pte_t *ptep = pte_offset_kernel(pmdp, start);
294
294
295
-
for (i = 0; i < PTRS_PER_PTE; i++, ptep++) {
296
-
addr = start + i * PAGE_SIZE;
295
+
do {
297
296
note_page(st, addr, 4, READ_ONCE(pte_val(*ptep)));
298
-
}
297
+
} while (ptep++, addr += PAGE_SIZE, addr != end);
299
298
}
300
299
301
-
static void walk_pmd(struct pg_state *st, pud_t *pudp, unsigned long start)
300
+
static void walk_pmd(struct pg_state *st, pud_t *pudp, unsigned long start,
301
+
unsigned long end)
302
302
{
303
-
pmd_t *pmdp = pmd_offset(pudp, 0UL);
304
-
unsigned long addr;
305
-
unsigned i;
303
+
unsigned long next, addr = start;
304
+
pmd_t *pmdp = pmd_offset(pudp, start);
306
305
307
-
for (i = 0; i < PTRS_PER_PMD; i++, pmdp++) {
306
+
do {
308
307
pmd_t pmd = READ_ONCE(*pmdp);
308
+
next = pmd_addr_end(addr, end);
309
309
310
-
addr = start + i * PMD_SIZE;
311
310
if (pmd_none(pmd) || pmd_sect(pmd)) {
312
311
note_page(st, addr, 3, pmd_val(pmd));
313
312
} else {
314
313
BUG_ON(pmd_bad(pmd));
315
-
walk_pte(st, pmdp, addr);
314
+
walk_pte(st, pmdp, addr, next);
316
315
}
317
-
}
316
+
} while (pmdp++, addr = next, addr != end);
318
317
}
319
318
320
-
static void walk_pud(struct pg_state *st, pgd_t *pgdp, unsigned long start)
319
+
static void walk_pud(struct pg_state *st, pgd_t *pgdp, unsigned long start,
320
+
unsigned long end)
321
321
{
322
-
pud_t *pudp = pud_offset(pgdp, 0UL);
323
-
unsigned long addr;
324
-
unsigned i;
322
+
unsigned long next, addr = start;
323
+
pud_t *pudp = pud_offset(pgdp, start);
325
324
326
-
for (i = 0; i < PTRS_PER_PUD; i++, pudp++) {
325
+
do {
327
326
pud_t pud = READ_ONCE(*pudp);
327
+
next = pud_addr_end(addr, end);
328
328
329
-
addr = start + i * PUD_SIZE;
330
329
if (pud_none(pud) || pud_sect(pud)) {
331
330
note_page(st, addr, 2, pud_val(pud));
332
331
} else {
333
332
BUG_ON(pud_bad(pud));
334
-
walk_pmd(st, pudp, addr);
333
+
walk_pmd(st, pudp, addr, next);
335
334
}
336
-
}
335
+
} while (pudp++, addr = next, addr != end);
337
336
}
338
337
339
338
static void walk_pgd(struct pg_state *st, struct mm_struct *mm,
340
339
unsigned long start)
341
340
{
342
-
pgd_t *pgdp = pgd_offset(mm, 0UL);
343
-
unsigned i;
344
-
unsigned long addr;
341
+
unsigned long end = (start < TASK_SIZE_64) ? TASK_SIZE_64 : 0;
342
+
unsigned long next, addr = start;
343
+
pgd_t *pgdp = pgd_offset(mm, start);
345
344
346
-
for (i = 0; i < PTRS_PER_PGD; i++, pgdp++) {
345
+
do {
347
346
pgd_t pgd = READ_ONCE(*pgdp);
347
+
next = pgd_addr_end(addr, end);
348
348
349
-
addr = start + i * PGDIR_SIZE;
350
349
if (pgd_none(pgd)) {
351
350
note_page(st, addr, 1, pgd_val(pgd));
352
351
} else {
353
352
BUG_ON(pgd_bad(pgd));
354
-
walk_pud(st, pgdp, addr);
353
+
walk_pud(st, pgdp, addr, next);
355
354
}
356
-
}
355
+
} while (pgdp++, addr = next, addr != end);
357
356
}
358
357
359
358
void ptdump_walk_pgd(struct seq_file *m, struct ptdump_info *info)