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[v2,0/3] kmod: modprobe: Extend holders removal to multi-level dependencies

Message ID 20230309-remove-holders-recursively-v2-0-8a8120269cc1@avm.de (mailing list archive)
Headers show
Series kmod: modprobe: Extend holders removal to multi-level dependencies | expand

Message

Nicolas Schier March 29, 2023, 1:51 p.m. UTC 
While commit 42b32d30c38e ("modprobe: Fix holders removal", 2022-03-29) already
implements removing first-level holders, indirect holders were not evaluated.
In a simple module dependency chain like

      module3 depends on module2
      module2 depends on module1

'modprobe -r --remove-holders module1' was only considering module2 and module1
and thus had to fail as module3 was still loaded and blocking removal of
module2.

By doing recursive depth-first removal this can be fixed for such simple
dependency.

(modprobe.8 man page is not touched as it does not yet have anything
about --remove-holders.)

Signed-off-by: Nicolas Schier <n.schier@avm.de>
---
To: linux-modules@vger.kernel.org
Cc: Lucas De Marchi <lucas.de.marchi@gmail.com>

---
Changes in v2:
 * Several fixes (memleak, attempt to remove modules that were just
   removed, --dry-run support)
 * new patch: Add rudimentary implementation of sysfs tree modification
   to delete_module()
 * new patch: Add two tests regarding --remove-holders to
   testsuite/test-modprobe.c
 * Link to v1: https://lore.kernel.org/r/20230309-remove-holders-recursively-v1-1-c27cdba1edbf@avm.de

---
Nicolas Schier (3):
      kmod: modprobe: Remove holders recursively
      testsuite: delete_module: Roughly implement fake-removal in sysfs tree
      testsuite: modprobe: Add test for --remove-holders

 Makefile.am                                        |   1 +
 testsuite/delete_module.c                          | 262 ++++++++++++++++++++-
 testsuite/module-playground/Makefile               |   6 +
 testsuite/module-playground/mod-dep-chain-a.c      |  21 ++
 testsuite/module-playground/mod-dep-chain-b.c      |  22 ++
 testsuite/module-playground/mod-dep-chain-c.c      |  22 ++
 testsuite/module-playground/mod-dep-chain.h        |   8 +
 .../remove-holders/lib/modules/6.2/modules.alias   |   1 +
 .../lib/modules/6.2/modules.alias.bin              | Bin 0 -> 12 bytes
 .../lib/modules/6.2/modules.builtin.alias.bin      |   0
 .../lib/modules/6.2/modules.builtin.bin            |   0
 .../remove-holders/lib/modules/6.2/modules.dep     |   3 +
 .../remove-holders/lib/modules/6.2/modules.dep.bin | Bin 0 -> 229 bytes
 .../remove-holders/lib/modules/6.2/modules.devname |   0
 .../remove-holders/lib/modules/6.2/modules.softdep |   1 +
 .../remove-holders/lib/modules/6.2/modules.symbols |   4 +
 .../lib/modules/6.2/modules.symbols.bin            | Bin 0 -> 143 bytes
 .../test-modprobe/remove-holders/proc/modules      |   3 +
 .../sys/module/mod_dep_chain_a/coresize            |   1 +
 .../module/mod_dep_chain_a/holders/mod_dep_chain_b |   1 +
 .../sys/module/mod_dep_chain_a/initsize            |   1 +
 .../sys/module/mod_dep_chain_a/initstate           |   1 +
 .../sys/module/mod_dep_chain_a/notes/.note.Linux   | Bin 0 -> 60 bytes
 .../mod_dep_chain_a/notes/.note.gnu.build-id       | Bin 0 -> 36 bytes
 .../sys/module/mod_dep_chain_a/refcnt              |   1 +
 .../sections/.gnu.linkonce.this_module             |   1 +
 .../sys/module/mod_dep_chain_a/sections/.init.data |   1 +
 .../module/mod_dep_chain_a/sections/.note.Linux    |   1 +
 .../mod_dep_chain_a/sections/.note.gnu.build-id    |   1 +
 .../module/mod_dep_chain_a/sections/.orc_unwind    |   1 +
 .../module/mod_dep_chain_a/sections/.orc_unwind_ip |   1 +
 .../module/mod_dep_chain_a/sections/.return_sites  |   1 +
 .../module/mod_dep_chain_a/sections/.rodata.str1.1 |   1 +
 .../sys/module/mod_dep_chain_a/sections/.strtab    |   1 +
 .../sys/module/mod_dep_chain_a/sections/.symtab    |   1 +
 .../module/mod_dep_chain_a/sections/.text.unlikely |   1 +
 .../sys/module/mod_dep_chain_a/sections/__kcrctab  |   1 +
 .../sys/module/mod_dep_chain_a/sections/__ksymtab  |   1 +
 .../mod_dep_chain_a/sections/__ksymtab_strings     |   1 +
 .../module/mod_dep_chain_a/sections/__mcount_loc   |   1 +
 .../sys/module/mod_dep_chain_a/taint               |   1 +
 .../sys/module/mod_dep_chain_b/coresize            |   1 +
 .../module/mod_dep_chain_b/holders/mod_dep_chain_c |   1 +
 .../sys/module/mod_dep_chain_b/initsize            |   1 +
 .../sys/module/mod_dep_chain_b/initstate           |   1 +
 .../sys/module/mod_dep_chain_b/notes/.note.Linux   | Bin 0 -> 60 bytes
 .../mod_dep_chain_b/notes/.note.gnu.build-id       | Bin 0 -> 36 bytes
 .../sys/module/mod_dep_chain_b/refcnt              |   1 +
 .../sections/.gnu.linkonce.this_module             |   1 +
 .../sys/module/mod_dep_chain_b/sections/.init.data |   1 +
 .../module/mod_dep_chain_b/sections/.note.Linux    |   1 +
 .../mod_dep_chain_b/sections/.note.gnu.build-id    |   1 +
 .../module/mod_dep_chain_b/sections/.orc_unwind    |   1 +
 .../module/mod_dep_chain_b/sections/.orc_unwind_ip |   1 +
 .../module/mod_dep_chain_b/sections/.return_sites  |   1 +
 .../module/mod_dep_chain_b/sections/.rodata.str1.8 |   1 +
 .../sys/module/mod_dep_chain_b/sections/.strtab    |   1 +
 .../sys/module/mod_dep_chain_b/sections/.symtab    |   1 +
 .../module/mod_dep_chain_b/sections/.text.unlikely |   1 +
 .../sys/module/mod_dep_chain_b/sections/__kcrctab  |   1 +
 .../sys/module/mod_dep_chain_b/sections/__ksymtab  |   1 +
 .../mod_dep_chain_b/sections/__ksymtab_strings     |   1 +
 .../module/mod_dep_chain_b/sections/__mcount_loc   |   1 +
 .../sys/module/mod_dep_chain_b/taint               |   1 +
 .../sys/module/mod_dep_chain_c/coresize            |   1 +
 .../sys/module/mod_dep_chain_c/holders/.gitignore  |   0
 .../sys/module/mod_dep_chain_c/initsize            |   1 +
 .../sys/module/mod_dep_chain_c/initstate           |   1 +
 .../sys/module/mod_dep_chain_c/notes/.note.Linux   | Bin 0 -> 60 bytes
 .../mod_dep_chain_c/notes/.note.gnu.build-id       | Bin 0 -> 36 bytes
 .../sys/module/mod_dep_chain_c/refcnt              |   1 +
 .../sys/module/mod_dep_chain_c/taint               |   1 +
 .../remove-single/lib/modules/6.2/modules.alias    |   1 +
 .../lib/modules/6.2/modules.alias.bin              | Bin 0 -> 12 bytes
 .../lib/modules/6.2/modules.builtin.alias.bin      |   0
 .../lib/modules/6.2/modules.builtin.bin            |   0
 .../remove-single/lib/modules/6.2/modules.dep      |   3 +
 .../remove-single/lib/modules/6.2/modules.dep.bin  | Bin 0 -> 229 bytes
 .../remove-single/lib/modules/6.2/modules.devname  |   0
 .../remove-single/lib/modules/6.2/modules.softdep  |   1 +
 .../remove-single/lib/modules/6.2/modules.symbols  |   4 +
 .../lib/modules/6.2/modules.symbols.bin            | Bin 0 -> 143 bytes
 .../test-modprobe/remove-single/proc/modules       |   3 +
 .../sys/module/mod_dep_chain_a/coresize            |   1 +
 .../module/mod_dep_chain_a/holders/mod_dep_chain_b |   1 +
 .../sys/module/mod_dep_chain_a/initsize            |   1 +
 .../sys/module/mod_dep_chain_a/initstate           |   1 +
 .../sys/module/mod_dep_chain_a/notes/.note.Linux   | Bin 0 -> 60 bytes
 .../mod_dep_chain_a/notes/.note.gnu.build-id       | Bin 0 -> 36 bytes
 .../sys/module/mod_dep_chain_a/refcnt              |   1 +
 .../sections/.gnu.linkonce.this_module             |   1 +
 .../sys/module/mod_dep_chain_a/sections/.init.data |   1 +
 .../module/mod_dep_chain_a/sections/.note.Linux    |   1 +
 .../mod_dep_chain_a/sections/.note.gnu.build-id    |   1 +
 .../module/mod_dep_chain_a/sections/.orc_unwind    |   1 +
 .../module/mod_dep_chain_a/sections/.orc_unwind_ip |   1 +
 .../module/mod_dep_chain_a/sections/.return_sites  |   1 +
 .../module/mod_dep_chain_a/sections/.rodata.str1.1 |   1 +
 .../sys/module/mod_dep_chain_a/sections/.strtab    |   1 +
 .../sys/module/mod_dep_chain_a/sections/.symtab    |   1 +
 .../module/mod_dep_chain_a/sections/.text.unlikely |   1 +
 .../sys/module/mod_dep_chain_a/sections/__kcrctab  |   1 +
 .../sys/module/mod_dep_chain_a/sections/__ksymtab  |   1 +
 .../mod_dep_chain_a/sections/__ksymtab_strings     |   1 +
 .../module/mod_dep_chain_a/sections/__mcount_loc   |   1 +
 .../remove-single/sys/module/mod_dep_chain_a/taint |   1 +
 .../sys/module/mod_dep_chain_b/coresize            |   1 +
 .../module/mod_dep_chain_b/holders/mod_dep_chain_c |   1 +
 .../sys/module/mod_dep_chain_b/initsize            |   1 +
 .../sys/module/mod_dep_chain_b/initstate           |   1 +
 .../sys/module/mod_dep_chain_b/notes/.note.Linux   | Bin 0 -> 60 bytes
 .../mod_dep_chain_b/notes/.note.gnu.build-id       | Bin 0 -> 36 bytes
 .../sys/module/mod_dep_chain_b/refcnt              |   1 +
 .../sections/.gnu.linkonce.this_module             |   1 +
 .../sys/module/mod_dep_chain_b/sections/.init.data |   1 +
 .../module/mod_dep_chain_b/sections/.note.Linux    |   1 +
 .../mod_dep_chain_b/sections/.note.gnu.build-id    |   1 +
 .../module/mod_dep_chain_b/sections/.orc_unwind    |   1 +
 .../module/mod_dep_chain_b/sections/.orc_unwind_ip |   1 +
 .../module/mod_dep_chain_b/sections/.return_sites  |   1 +
 .../module/mod_dep_chain_b/sections/.rodata.str1.8 |   1 +
 .../sys/module/mod_dep_chain_b/sections/.strtab    |   1 +
 .../sys/module/mod_dep_chain_b/sections/.symtab    |   1 +
 .../module/mod_dep_chain_b/sections/.text.unlikely |   1 +
 .../sys/module/mod_dep_chain_b/sections/__kcrctab  |   1 +
 .../sys/module/mod_dep_chain_b/sections/__ksymtab  |   1 +
 .../mod_dep_chain_b/sections/__ksymtab_strings     |   1 +
 .../module/mod_dep_chain_b/sections/__mcount_loc   |   1 +
 .../remove-single/sys/module/mod_dep_chain_b/taint |   1 +
 .../sys/module/mod_dep_chain_c/coresize            |   1 +
 .../sys/module/mod_dep_chain_c/holders/.gitignore  |   0
 .../sys/module/mod_dep_chain_c/initsize            |   1 +
 .../sys/module/mod_dep_chain_c/initstate           |   1 +
 .../sys/module/mod_dep_chain_c/notes/.note.Linux   | Bin 0 -> 60 bytes
 .../mod_dep_chain_c/notes/.note.gnu.build-id       | Bin 0 -> 36 bytes
 .../sys/module/mod_dep_chain_c/refcnt              |   1 +
 .../remove-single/sys/module/mod_dep_chain_c/taint |   1 +
 testsuite/setup-rootfs.sh                          |   3 +
 testsuite/test-modprobe.c                          |  55 +++++
 tools/modprobe.c                                   |  44 +++-
 140 files changed, 551 insertions(+), 11 deletions(-)
---
base-commit: 3d1bd339ab942ea47e60f053f4b11b0c47ff082b
change-id: 20230309-remove-holders-recursively-f667f32e2a7d

Best regards,